10 shuffling question

[pt wee]

I am new to java, can anyone help me out?
I use random method, sometime same question appear on the applet.
Try using shuffling method but don't know how to do.

java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import java.lang.Math;
   
    public class RegularArray extends JApplet implements ItemListener,ActionListener {
        int face;
        int a;
        
    public void init() {
        for(int roll=1; roll<=10; roll++) {
            face = 1 + (int) (Math.random()*30);
            switch (face) {
                case 1:q1();break; case 2:q2();break; case 3:q3();break; case 4:q4();break; case 5:q5();break; 
                case 6:q6();break; case 7:q7();break; case 8:q8();break; case 9:q9();break; case 10:q10();break;
                case 11:q11();break; case 12:q12();break; case 13:q13();break; case 14:q14();break; case 15:q15();break; 
                case 16:q16();break; case 17:q17();break; case 18:q18();break; case 19:q19();break; case 20:q20();break;
                case 21:q21();break; case 22:q22();break; case 23:q23();break; case 24:q24();break; case 25:q25();break; 
                case 26:q26();break; case 27:q27();break; case 28:q28();break; case 29:q29();break; case 30:q30();break;
                }
            }
            Container contentPane0 = getContentPane();
            contentPane0.setLayout(new GridLayout(0,1));
            Button jb = new Button("Well... How did I do?=)");
            jb.setFont(new Font("Serif", Font.BOLD,11));
            contentPane0.add(jb);
            jb.addActionListener(this);
        }
    public void q1() {
        Container contentPane1 = getContentPane();
        contentPane1.setLayout(new GridLayout(0,1));
        JLabel label1 = new JLabel("What does NEM stands for?");
        label1.setForeground(Color.blue);
        contentPane1.add(label1);
        JRadioButton b1a = new JRadioButton("a) New Electricity Market");
        contentPane1.add(b1a);
        JRadioButton b1b = new JRadioButton("b) New Energy Market");
        contentPane1.add(b1b);
        JRadioButton b1c = new JRadioButton("c) New Environment Market");
        contentPane1.add(b1c);
        JRadioButton b1d = new JRadioButton("d) New Economy Market");
        contentPane1.add(b1d);
        JLabel label1S = new JLabel("");
        contentPane1.add(label1S);
        ButtonGroup bg1 = new ButtonGroup();
        bg1.add(b1a);
        bg1.add(b1b);
        b1b.addItemListener(this);
        bg1.add(b1c);
        bg1.add(b1d);
        }
    public void q2() {
        Container contentPane2 = getContentPane();
        contentPane2.setLayout(new GridLayout(0,1));
        JLabel label2 = new JLabel("When did NEM first commerence?");
        label2.setForeground(Color.blue);
        contentPane2.add(label2);
        JRadioButton b2a = new JRadioButton("a) 1st Feb 2003");
        contentPane2.add(b2a);
        JRadioButton b2b = new JRadioButton("b) 1st Jan 2002");
        contentPane2.add(b2b);
        JRadioButton b2c = new JRadioButton("c) 1st Jan 2003");
        contentPane2.add(b2c);
        JRadioButton b2d = new JRadioButton("d) 1st Feb 2002");
        contentPane2.add(b2d);
        JLabel label2S = new JLabel("");
        contentPane2.add(label2S);
        ButtonGroup bg2 = new ButtonGroup();
        bg2.add(b2a);
        bg2.add(b2b);
        b2b.addItemListener(this);
        bg2.add(b2c);
        bg2.add(b2d);
        }
        public void q3() {
        Container contentPane3 = getContentPane();
        contentPane3.setLayout(new GridLayout(0,1));
        JLabel label3 = new JLabel("The NEM consists of two markets. They are...");
        label3.setForeground(Color.blue);
        contentPane3.add(label3);
        JRadioButton b3a = new JRadioButton("a) Fair Price and NTUC markets");
        contentPane3.add(b3a);
        JRadioButton b3b = new JRadioButton("b) Flow and Line markets");
        contentPane3.add(b3b);
        JRadioButton b3c = new JRadioButton("c) Real-time and Spot markets");
        contentPane3.add(b3c);
        JRadioButton b3d = new JRadioButton("d) Electronic and Electrical markets");
        contentPane3.add(b3d);
        JLabel label3S = new JLabel("");
        contentPane3.add(label3S);
        ButtonGroup bg3 = new ButtonGroup();
        bg3.add(b3a);
        bg3.add(b3b);
        b3b.addItemListener(this);
        bg3.add(b3c);
        bg3.add(b3d);
        }
        public void q4() {
        Container contentPane4 = getContentPane();
        contentPane4.setLayout(new GridLayout(0,1));
        JLabel label4 = new JLabel("Name 3 key players in Electricity market. They are...");
        label4.setForeground(Color.blue);
        contentPane4.add(label4);
        JRadioButton b4a = new JRadioButton("a) Retailers, Investors and Market operators.");
        contentPane4.add(b4a);
        JRadioButton b4b = new JRadioButton("b) Transmission Licensees, Power System Operators and Generation Licensees");
        contentPane4.add(b4b);
        JRadioButton b4c = new JRadioButton("c) Market operators, Transmission Licensees and Generation Licensees");
        contentPane4.add(b4c);
        JRadioButton b4d = new JRadioButton("d) Public Utilities Board, Energy Market Authority and Temasek Holdings");
        contentPane4.add(b4d);
        JLabel label4S = new JLabel("");
        contentPane4.add(label4S);
        ButtonGroup bg4 = new ButtonGroup();
        bg4.add(b4a);
        bg4.add(b4b);
        b4b.addItemListener(this);
        bg4.add(b4c);
        bg4.add(b4d);
        }
        public void q5() {
        Container contentPane5 = getContentPane();
        contentPane5.setLayout(new GridLayout(0,1));
        JLabel label5 = new JLabel("Singapore consists of two separate gas systems. What are they?");
        label5.setForeground(Color.blue);
        contentPane5.add(label5);
        JRadioButton b5a = new JRadioButton("a) Town gas and Natural gas");
        contentPane5.add(b5a);
        JRadioButton b5b = new JRadioButton("b) Natural and Universal gas");
        contentPane5.add(b5b);
        JRadioButton b5c = new JRadioButton("c) Town gas and City gas");
        contentPane5.add(b5c);
        JRadioButton b5d = new JRadioButton("d) City gas and Unnatural gas");
        contentPane5.add(b5d);
        JLabel label5S = new JLabel("");
        contentPane5.add(label5S);
        ButtonGroup bg5 = new ButtonGroup();
        bg5.add(b5a);
        bg5.add(b5b);
        b5b.addItemListener(this);
        bg5.add(b5c);
        bg5.add(b5d);
        }
        public void q6() {
        Container contentPane6 = getContentPane();
        contentPane6.setLayout(new GridLayout(0,1));
        JLabel label6 = new JLabel("What are the countries does SPC operates other than in Singapore?");
        label6.setForeground(Color.blue);
        contentPane6.add(label6);
        JRadioButton b6a = new JRadioButton("a) Hong Kong, America and India");
        contentPane6.add(b6a);
        JRadioButton b6b = new JRadioButton("b) Afghanistan, Canada and Australia");
        contentPane6.add(b6b);
        JRadioButton b6c = new JRadioButton("c) Spain, France and Russia");
        contentPane6.add(b6c);
        JRadioButton b6d = new JRadioButton("d) China, Hong Kong and Malaysia");
        contentPane6.add(b6d);
        JLabel label6S = new JLabel("");
        contentPane6.add(label6S);
        ButtonGroup bg6 = new ButtonGroup();
        bg6.add(b6a);
        bg6.add(b6b);
        b6b.addItemListener(this);
        bg6.add(b6c);
        bg6.add(b6d);
        }
        public void q7() {
        Container contentPane7 = getContentPane();
        contentPane7.setLayout(new GridLayout(0,1));
        JLabel label7 = new JLabel("What are the companies that deals with generation?");
        label7.setForeground(Color.blue);
        contentPane7.add(label7);
        JRadioButton b7a = new JRadioButton("a) Singapore Technologies and ASSE Technologies");
        contentPane7.add(b7a);
        JRadioButton b7b = new JRadioButton("b) Sembcrop and Tuas Power");
        contentPane7.add(b7b);
        JRadioButton b7c = new JRadioButton("c) Xerox Pte Ltd and Overseas United Bank");
        contentPane7.add(b7c);
        JRadioButton b7d = new JRadioButton("d) Island Power Company and National Environment Agency");
        contentPane7.add(b7d);
        JLabel label7S = new JLabel("");
        contentPane7.add(label7S);
        ButtonGroup bg7 = new ButtonGroup();
        bg7.add(b7a);
        bg7.add(b7b);
        b7b.addItemListener(this);
        bg7.add(b7c);
        bg7.add(b7d);
        }
        public void q8() {
        Container contentPane8 = getContentPane();
        contentPane8.setLayout(new GridLayout(0,1));
        JLabel label8 = new JLabel("What are the imported energy sources and primarily are used for?");
        label8.setForeground(Color.blue);
        contentPane8.add(label8);
        JRadioButton b8a = new JRadioButton("a) Refining, Petrolchecmical and Power generation");
        contentPane8.add(b8a);
        JRadioButton b8b = new JRadioButton("b) Oil Refineries, Power generation and oil generation");
        contentPane8.add(b8b);
        JRadioButton b8c = new JRadioButton("c) Water supply, Electricity supply and Building industries");
        contentPane8.add(b8c);
        JRadioButton b8d = new JRadioButton("d) Fuel production, Refining and Petrolchecmical");
        contentPane8.add(b8d);
        JLabel label8S = new JLabel("");
        contentPane8.add(label8S);
        ButtonGroup bg8 = new ButtonGroup();
        bg8.add(b8a);
        bg8.add(b8b);
        b8b.addItemListener(this);
        bg8.add(b8c);
        bg8.add(b8d);
        }
        public void q9() {
        Container contentPane9 = getContentPane();
        contentPane9.setLayout(new GridLayout(0,1));
        JLabel label9 = new JLabel("The Gas transportation business is separated into three sectors. They are...");
        label9.setForeground(Color.blue);
        contentPane9.add(label9);
        JRadioButton b9a = new JRadioButton("a) Generation, Transmission and Investment");
        contentPane9.add(b9a);
        JRadioButton b9b = new JRadioButton("b) Gas import, Trading and Retailing");
        contentPane9.add(b9b);
        JRadioButton b9c = new JRadioButton("c) Fuel export, gas import and oil import");
        contentPane9.add(b9c);
        JRadioButton b9d = new JRadioButton("d) Overseas market, local market and International market");
        contentPane9.add(b9d);
        JLabel label9S = new JLabel("");
        contentPane9.add(label9S);
        ButtonGroup bg9 = new ButtonGroup();
        bg9.add(b9a);
        bg9.add(b9b);
        b9b.addItemListener(this);
        bg9.add(b9c);
        bg9.add(b9d);
        }
        public void q10() {
        Container contentPane10 = getContentPane();
        contentPane10.setLayout(new GridLayout(0,1));
        JLabel label0 = new JLabel("The Gas Network is a multilateral agreement which sets out the common terms 
        apply to ...");
        label0.setForeground(Color.blue);
        contentPane10.add(label0);
        JRadioButton b0a = new JRadioButton("a) Exporters and Importers of gas in the gas pipeline network");
        contentPane10.add(b0a);
        JRadioButton b0b = new JRadioButton("b) Retailers and Shippers of gas in the gas pipeline network");
        contentPane10.add(b0b);
        JRadioButton b0c = new JRadioButton("c) Transporters and Shippers of gas in the gas pipeline network");
        contentPane10.add(b0c);
        JRadioButton b0d = new JRadioButton("d) Buyers and Shippers of gas in the gas pipeline network");
        contentPane10.add(b0d);
        JLabel label10S = new JLabel("");
        contentPane10.add(label10S);
        ButtonGroup bg0 = new ButtonGroup();
        bg0.add(b0a);
        bg0.add(b0b);
        b0b.addItemListener(this);
        bg0.add(b0c);
        bg0.add(b0d);
        }
        
        public void q11() {
        Container contentPane11 = getContentPane();
        contentPane11.setLayout(new GridLayout(0,1));
        JLabel label11 = new JLabel("Which one of the following is incorrect?");
        label11.setForeground(Color.blue);
        contentPane11.add(label11);
        JLabel label11a = new JLabel("The New Energy Market is designed to...");
        label11a.setForeground(Color.blue);
        contentPane11.add(label11a);
        JRadioButton b11a = new JRadioButton("a) Promote the efficient supply of competitively priced energy sources 
        such as electricity, gas and oil etc. ");
        contentPane11.add(b11a);
        JRadioButton b11b = new JRadioButton("b) Open up the retail market to full competition");
        contentPane11.add(b11b);
        JRadioButton b11c = new JRadioButton("c) Allow certain government-owned assets to be privatised");
        contentPane11.add(b11c);
        JRadioButton b11d = new JRadioButton("d) Encourage public investment in Singapore power and gas system 
        infrastructure");
        contentPane11.add(b11d);
        JLabel label11S = new JLabel("");
        contentPane11.add(label11S);
        ButtonGroup bg11 = new ButtonGroup();
        bg11.add(b11a);
        bg11.add(b11b);
        b11b.addItemListener(this);
        bg11.add(b11c);
        bg11.add(b11d);
        }
        public void q12() {
        Container contentPane12 = getContentPane();
        contentPane12.setLayout(new GridLayout(0,1));
        JLabel label12 = new JLabel("How many choices to commence purchasing electricity does Contestable Consumers 
        have with monthly bill above $3000?");
        label12.setForeground(Color.blue);
        contentPane12.add(label12);
        JRadioButton b12a = new JRadioButton("a) 1");
        contentPane12.add(b12a);
        JRadioButton b12b = new JRadioButton("b) 3");
        contentPane12.add(b12b);
        JRadioButton b12c = new JRadioButton("c) 5");
        contentPane12.add(b12c);
        JRadioButton b12d = new JRadioButton("d) 2");
        contentPane12.add(b12d);
        JLabel label12S = new JLabel("");
        contentPane12.add(label12S);
        ButtonGroup bg12 = new ButtonGroup();
        bg12.add(b12a);
        bg12.add(b12b);
        b12b.addItemListener(this);
        bg12.add(b12c);
        bg12.add(b12d);
        }
        public void q13() {
        Container contentPane13 = getContentPane();
        contentPane13.setLayout(new GridLayout(0,1));
        JLabel label13 = new JLabel("How does Power Grid function in Singapore?");
        label13.setForeground(Color.blue);
        contentPane13.add(label13);
        JRadioButton b13a = new JRadioButton("a) The owner and operator of the gas transmission network");
        contentPane13.add(b13a);
        JRadioButton b13b = new JRadioButton("b) A holding company for the transmission company , the utilities/supply 
        support services company");
        contentPane13.add(b13b);
        JRadioButton b13c = new JRadioButton("c) Owns and operates and maintains the transmission system");
        contentPane13.add(b13c);
        JRadioButton b13d = new JRadioButton("d) The supplier for all non-contestable consumers and, also contestable 
        consumer who does not, cannot or no longer wishes to purchase electricity from a retailer or wholesale market");
        contentPane13.add(b13d);
        JLabel label13S = new JLabel("");
        contentPane13.add(label13S);
        ButtonGroup bg13 = new ButtonGroup();
        bg13.add(b13a);
        bg13.add(b13b);
        b13b.addItemListener(this);
        bg13.add(b13c);
        bg13.add(b13d);
        }
        public void q14() {
        Container contentPane14 = getContentPane();
        contentPane14.setLayout(new GridLayout(0,1));
        JLabel label14 = new JLabel("What type of energy is Singapore using?");
        label14.setForeground(Color.blue);
        contentPane14.add(label14);
        JRadioButton b14a = new JRadioButton("a) Electricity");
        contentPane14.add(b14a);
        JRadioButton b14b = new JRadioButton("b) Natural Gas");
        contentPane14.add(b14b);
        JRadioButton b14c = new JRadioButton("c) Crude oil and Petroleum");
        contentPane14.add(b14c);
        JRadioButton b14d = new JRadioButton("d) all of the above");
        contentPane14.add(b14d);
        JLabel label14S = new JLabel("");
        contentPane14.add(label14S);
        ButtonGroup bg14 = new ButtonGroup();
        bg14.add(b14a);
        bg14.add(b14b);
        b14b.addItemListener(this);
        bg14.add(b14c);
        bg14.add(b14d);
        }
        public void q15() {
        Container contentPane15 = getContentPane();
        contentPane15.setLayout(new GridLayout(0,1));
        JLabel label15 = new JLabel("Which is the incorrect description of a market participant should be?");
        label15.setForeground(Color.blue);
        contentPane15.add(label15);
        JRadioButton b15a = new JRadioButton("a) Power licensees");
        contentPane15.add(b15a);
        JRadioButton b15b = new JRadioButton("b) Generation licensees");
        contentPane15.add(b15b);
        JRadioButton b15c = new JRadioButton("c) Retail electricity licensees");
        contentPane15.add(b15c);
        JRadioButton b15d = new JRadioButton("d) transmission licensee");
        contentPane15.add(b15d);
        JLabel label15S = new JLabel("");
        contentPane15.add(label15S);
        ButtonGroup bg15 = new ButtonGroup();
        bg15.add(b15a);
        bg15.add(b15b);
        b15b.addItemListener(this);
        bg15.add(b15c);
        bg15.add(b15d);
        }
        public void q16() {
        Container contentPane16 = getContentPane();
        contentPane16.setLayout(new GridLayout(0,1));
        JLabel label16 = new JLabel("At the commencement of the NEM, how many market participant(s) are there it is 
        expected in the wholesale market?");
        label16.setForeground(Color.blue);
        contentPane16.add(label16);
        JRadioButton b16a = new JRadioButton("a) 13");
        contentPane16.add(b16a);
        JRadioButton b16b = new JRadioButton("b) 14");
        contentPane16.add(b16b);
        JRadioButton b16c = new JRadioButton("c) 15");
        contentPane16.add(b16c);
        JRadioButton b16d = new JRadioButton("d) 16");
        contentPane16.add(b16d);
        JLabel label16S = new JLabel("");
        contentPane16.add(label16S);
        ButtonGroup bg16 = new ButtonGroup();
        bg16.add(b16a);
        bg16.add(b16b);
        b16b.addItemListener(this);
        bg16.add(b16c);
        bg16.add(b16d);
        }
        public void q17() {
        Container contentPane17 = getContentPane();
        contentPane17.setLayout(new GridLayout(0,1));
        JLabel label17 = new JLabel("What is the Generation (Non-fuel) Fixed Cost at?");
        label17.setForeground(Color.blue);
        contentPane17.add(label17);
        JRadioButton b17a = new JRadioButton("a) 16%");
        contentPane17.add(b17a);
        JRadioButton b17b = new JRadioButton("b) 23%");
        contentPane17.add(b17b);
        JRadioButton b17c = new JRadioButton("c) 33%");
        contentPane17.add(b17c);
        JRadioButton b17d = new JRadioButton("d) 46%");
        contentPane17.add(b17d);
        JLabel label17S = new JLabel("");
        contentPane17.add(label17S);
        ButtonGroup bg17 = new ButtonGroup();
        bg17.add(b17a);
        bg17.add(b17b);
        b17b.addItemListener(this);
        bg17.add(b17c);
        bg17.add(b17d);
        }
        public void q18() {
        Container contentPane18 = getContentPane();
        contentPane18.setLayout(new GridLayout(0,1));
        JLabel label18 = new JLabel("When is EMA formed officially?");
        label18.setForeground(Color.blue);
        contentPane18.add(label18);
        JRadioButton b18a = new JRadioButton("a) 1st Jan 2001");
        contentPane18.add(b18a);
        JRadioButton b18b = new JRadioButton("b) 1st Feb 2001");
        contentPane18.add(b18b);
        JRadioButton b18c = new JRadioButton("c) 1st Mar 2001");
        contentPane18.add(b18c);
        JRadioButton b18d = new JRadioButton("d) 1st Apr 2001");
        contentPane18.add(b18d);
        JLabel label18S = new JLabel("");
        contentPane18.add(label18S);
        ButtonGroup bg18 = new ButtonGroup();
        bg18.add(b18a);
        bg18.add(b18b);
        b18b.addItemListener(this);
        bg18.add(b18c);
        bg18.add(b18d);
        }
        public void q19() {
        Container contentPane19 = getContentPane();
        contentPane19.setLayout(new GridLayout(0,1));
        JLabel label19 = new JLabel("What is the definition of a gas licensee?");
        label19.setForeground(Color.blue);
        contentPane19.add(label19);
        JRadioButton b19a = new JRadioButton("a) A power inspector");
        contentPane19.add(b19a);
        JRadioButton b19b = new JRadioButton("b) A gas retailer and a gas transporters;");
        contentPane19.add(b19b);
        JRadioButton b19c = new JRadioButton("c) A gas retailer");
        contentPane19.add(b19c);
        JRadioButton b19d = new JRadioButton("d) A gas inspector");
        contentPane19.add(b19d);
        JLabel label19S = new JLabel("");
        contentPane19.add(label19S);
        ButtonGroup bg19 = new ButtonGroup();
        bg19.add(b19a);
        bg19.add(b19b);
        b19b.addItemListener(this);
        bg19.add(b19c);
        bg19.add(b19d);
        }
        public void q20() {
        Container contentPane20 = getContentPane();
        contentPane20.setLayout(new GridLayout(0,1));
        JLabel label20 = new JLabel("Who is Regulator?");
        label20.setForeground(Color.blue);
        contentPane20.add(label20);
        JRadioButton b20a = new JRadioButton("a) The EMA is the Regulator of the electricity sector and has the 
        ultimate responsibility for ensuring that the NEM meets the needs of Singapore.");
        contentPane20.add(b20a);
        JRadioButton b20b = new JRadioButton("b) The NEM is the Regulator of the electricity sector and has the 
        ultimate responsibility for ensuring that the EMA meets the needs of Singapore.");
        contentPane20.add(b20b);
        JRadioButton b20c = new JRadioButton("c) The EMA is the Regulator of the electricity sector and has the 
        ultimate responsibility for ensuring that the Contestables meets the needs of Singapore.");
        contentPane20.add(b20c);
        JRadioButton b20d = new JRadioButton("d) The Contestables is the Regulator of the electricity sector and 
        has the ultimate responsibility for ensuring that the NEM meets the needs of Singapore.");
        contentPane20.add(b20d);
        JLabel label20S = new JLabel("");
        contentPane20.add(label20S);
        ButtonGroup bg20 = new ButtonGroup();
        bg20.add(b20a);
        bg20.add(b20b);
        b20b.addItemListener(this);
        bg20.add(b20c);
        bg20.add(b20d);
        }
        public void q21() {
        Container contentPane21 = getContentPane();
        contentPane21.setLayout(new GridLayout(0,1));
        JLabel label21 = new JLabel("What is the structure of a wholesale market comprises of other markets?");
        label21.setForeground(Color.blue);
        contentPane21.add(label21);
        JRadioButton b21a = new JRadioButton("a) Energy market and Consumer market");
        contentPane21.add(b21a);
        JRadioButton b21b = new JRadioButton("b) Purchasing market and Retailing / Sale market");
        contentPane21.add(b21b);
        JRadioButton b21c = new JRadioButton("c) Real-time market / Spot market and Procurement market");
        contentPane21.add(b21c);
        JRadioButton b21d = new JRadioButton("d) Legal market and Contestable market");
        contentPane21.add(b21d);
        JLabel label21S = new JLabel("");
        contentPane21.add(label21S);
        ButtonGroup bg21 = new ButtonGroup();
        bg21.add(b21a);
        bg21.add(b21b);
        b21b.addItemListener(this);
        bg21.add(b21c);
        bg21.add(b21d);
        }
        public void q22() {
        Container contentPane22 = getContentPane();
        contentPane22.setLayout(new GridLayout(0,1));
        JLabel label22 = new JLabel("Which of the following is incorrect?");
        label22.setForeground(Color.blue);
        contentPane22.add(label22);
        JLabel label22a = new JLabel("Spot market determines�");
        label22a.setForeground(Color.blue);
        contentPane22.add(label22a);
        JRadioButton b22a = new JRadioButton("a) The dispatch quantity that each generation facility is to produce;");
        contentPane22.add(b22a);
        JRadioButton b22b = new JRadioButton("b) The reserve and regulation capacity required to be maintained by 
        each facility;");
        contentPane22.add(b22b);
        JRadioButton b22c = new JRadioButton("c) The corresponding wholesale spot market prices for energy, reserve 
        and regulation.");
        contentPane22.add(b22c);
        JRadioButton b22d = new JRadioButton("d) The supplier for all non-contestable consumers and, also contestable
        consumer who does not, cannot or no longer wishes to purchase electricity from a retailer or wholesale market");
        contentPane22.add(b22d);
        JLabel label22S = new JLabel("");
        contentPane22.add(label22S);
        ButtonGroup bg22 = new ButtonGroup();
        bg22.add(b22a);
        bg22.add(b22b);
        b22b.addItemListener(this);
        bg22.add(b22c);
        bg22.add(b22d);
        }
        public void q23() {
        Container contentPane23 = getContentPane();
        contentPane23.setLayout(new GridLayout(0,1));
        JLabel label23 = new JLabel("SembGas supply natural gas to large consumers in�");
        label23.setForeground(Color.blue);
        contentPane23.add(label23);
        JRadioButton b23a = new JRadioButton("a) Jurong and Pulau Ubin");
        contentPane23.add(b23a);
        JRadioButton b23b = new JRadioButton("b) Tuas and Jurong");
        contentPane23.add(b23b);
        JRadioButton b23c = new JRadioButton("c) Chua Chu Kang and Sembawang");
        contentPane23.add(b23c);
        JRadioButton b23d = new JRadioButton("d) Sembawang and Jurong");
        contentPane23.add(b23d);
        JLabel label23S = new JLabel("");
        contentPane23.add(label23S);
        ButtonGroup bg23 = new ButtonGroup();
        bg23.add(b23a);
        bg23.add(b23b);
        b23b.addItemListener(this);
        bg23.add(b23c);
        bg23.add(b23d);
        }
        public void q24() {
        Container contentPane24 = getContentPane();
        contentPane24.setLayout(new GridLayout(0,1));
        JLabel label24 = new JLabel("Which of the following is incorrect?");
        label24.setForeground(Color.blue);
        contentPane24.add(label24);
        JLabel label24a = new JLabel("Contestable consumers will need to do the following to switch to a new retailer:");
        label24a.setForeground(Color.blue);
        contentPane24.add(label24a);
        JRadioButton b24a = new JRadioButton("a) Serve notice for termination of existing supply contract to existing 
        retailer");
        contentPane24.add(b24a);
        JRadioButton b24b = new JRadioButton("b) Inform existing retailer of the name of the new retailer");
        contentPane24.add(b24b);
        JRadioButton b24c = new JRadioButton("c) Sign new supply contract with new retailer. The new retailer will 
        inform the consumer when the transfer is effected.");
        contentPane24.add(b24c);
        JRadioButton b24d = new JRadioButton("d) Register the Name to the EMA and NEM");
        contentPane24.add(b24d);
        JLabel label24S = new JLabel("");
        contentPane24.add(label24S);
        ButtonGroup bg24 = new ButtonGroup();
        bg24.add(b24a);
        bg24.add(b24b);
        b24b.addItemListener(this);
        bg24.add(b24c);
        bg24.add(b24d);
        }
        public void q25() {
        Container contentPane25 = getContentPane();
        contentPane25.setLayout(new GridLayout(0,1));
        JLabel label25 = new JLabel("What are the voltages available in Singapore substation?");
        label25.setForeground(Color.blue);
        contentPane25.add(label25);
        JRadioButton b25a = new JRadioButton("a) 230V, 415V and 6.6KV");
        contentPane25.add(b25a);
        JRadioButton b25b = new JRadioButton("b) 230V, 400V and 66KV");
        contentPane25.add(b25b);
        JRadioButton b25c = new JRadioButton("c) 230V, 415V and 66KV");
        contentPane25.add(b25c);
        JRadioButton b25d = new JRadioButton("d) 230V, 400V and 6.6KV");
        contentPane25.add(b25d);
        JLabel label25S = new JLabel("");
        contentPane25.add(label25S);
        ButtonGroup bg25 = new ButtonGroup();
        bg25.add(b25a);
        bg25.add(b25b);
        b25b.addItemListener(this);
        bg25.add(b25c);
        bg25.add(b25d);
        }
        public void q26() {
        Container contentPane26 = getContentPane();
        contentPane26.setLayout(new GridLayout(0,1));
        JLabel label26 = new JLabel("How many Substations are there containing 400KV?");
        label26.setForeground(Color.blue);
        contentPane26.add(label26);
        JRadioButton b26a = new JRadioButton("a) 3");
        contentPane26.add(b26a);
        JRadioButton b26b = new JRadioButton("b) 6");
        contentPane26.add(b26b);
        JRadioButton b26c = new JRadioButton("c) 9");
        contentPane26.add(b26c);
        JRadioButton b26d = new JRadioButton("d) 12");
        contentPane26.add(b26d);
        JLabel label26S = new JLabel("");
        contentPane26.add(label26S);
        ButtonGroup bg26 = new ButtonGroup();
        bg26.add(b26a);
        bg26.add(b26b);
        b26b.addItemListener(this);
        bg26.add(b26c);
        bg26.add(b26d);
        }
        public void q27() {
        Container contentPane27 = getContentPane();
        contentPane27.setLayout(new GridLayout(0,1));
        JLabel label27 = new JLabel("How many Internal Market Participants are there?");
        label27.setForeground(Color.blue);
        contentPane27.add(label27);
        JRadioButton b27a = new JRadioButton("a) none");
        contentPane27.add(b27a);
        JRadioButton b27b = new JRadioButton("b) 3");
        contentPane27.add(b27b);
        JRadioButton b27c = new JRadioButton("c) 5");
        contentPane27.add(b27c);
        JRadioButton b27d = new JRadioButton("d) 7");
        contentPane27.add(b27d);
        JLabel label27S = new JLabel("");
        contentPane27.add(label27S);
        ButtonGroup bg27 = new ButtonGroup();
        bg27.add(b27a);
        bg27.add(b27b);
        b27b.addItemListener(this);
        bg27.add(b27c);
        bg27.add(b27d);
        }
        public void q28() {
        Container contentPane28 = getContentPane();
        contentPane28.setLayout(new GridLayout(0,1));
        JLabel label28 = new JLabel("How many Generation Companies are there in Singapore?");
        label28.setForeground(Color.blue);
        contentPane28.add(label28);
        JRadioButton b28a = new JRadioButton("a) 5");
        contentPane28.add(b28a);
        JRadioButton b28b = new JRadioButton("b) 7");
        contentPane28.add(b28b);
        JRadioButton b28c = new JRadioButton("c) 9");
        contentPane28.add(b28c);
        JRadioButton b28d = new JRadioButton("d) 11");
        contentPane28.add(b28d);
        JLabel label28S = new JLabel("");
        contentPane28.add(label28S);
        ButtonGroup bg28 = new ButtonGroup();
        bg28.add(b28a);
        bg28.add(b28b);
        b28b.addItemListener(this);
        bg28.add(b28c);
        bg28.add(b28d);
        }
        public void q29() {
        Container contentPane29 = getContentPane();
        contentPane29.setLayout(new GridLayout(0,1));
        JLabel label29 = new JLabel("How many Retail Companies are there in Singapore?");
        label29.setForeground(Color.blue);
        contentPane29.add(label29);
        JRadioButton b29a = new JRadioButton("a) 7");
        contentPane29.add(b29a);
        JRadioButton b29b = new JRadioButton("b) 5");
        contentPane29.add(b29b);
        JRadioButton b29c = new JRadioButton("c) 3");
        contentPane29.add(b29c);
        JRadioButton b29d = new JRadioButton("d) 1");
        contentPane29.add(b29d);
        JLabel label29S = new JLabel("");
        contentPane29.add(label29S);
        ButtonGroup bg29 = new ButtonGroup();
        bg29.add(b29a);
        bg29.add(b29b);
        b29b.addItemListener(this);
        bg29.add(b29c);
        bg29.add(b29d);
        }
        public void q30() {
        Container contentPane30 = getContentPane();
        contentPane30.setLayout(new GridLayout(0,1));
        JLabel label30 = new JLabel("A gas pipeline linking Sakra Island in Singapore and Grissik in South Sumatra, 
        Indonesia was launched on Monday in Batam. How many years is the deal?");
        label30.setForeground(Color.blue);
        contentPane30.add(label30);
        JRadioButton b30a = new JRadioButton("a) 5 years");
        contentPane30.add(b30a);
        JRadioButton b30b = new JRadioButton("b) 10 years");
        contentPane30.add(b30b);
        JRadioButton b30c = new JRadioButton("c) 15 years");
        contentPane30.add(b30c);
        JRadioButton b30d = new JRadioButton("d) 20years");
        contentPane30.add(b30d);
        JLabel label30S = new JLabel("");
        contentPane30.add(label30S);
        ButtonGroup bg30 = new ButtonGroup();
        bg30.add(b30a);
        bg30.add(b30b);
        b30b.addItemListener(this);
        bg30.add(b30c);
        bg30.add(b30d);
        }
        
        public void itemStateChanged(ItemEvent ie) {
            if(ie.getStateChange() == ItemEvent.DESELECTED)
            a -= 1;
            else
            a += 1;
        }
        public void actionPerformed(ActionEvent ae) {
            if(a<=0){JOptionPane.showMessageDialog(null,"You have yet to understand the Energy Market.");}
        else if(a>=1 && a <=4){JOptionPane.showMessageDialog(null,"You need a bit more understanding of 
        Energy Market.");}
        else if(a>=5 && a <=5){JOptionPane.showMessageDialog(null,"U are going fine");}
        else if(a>=6 && a <=7){JOptionPane.showMessageDialog(null,"U are getting there.");}
        else if(a>=8 && a <=9){JOptionPane.showMessageDialog(null,"U are almost there.");}
        else if(a>=10 && a <=10){JOptionPane.showMessageDialog(null,"Congrats! You have a clearer picture 
        of Energy Market now!");} 
        }

(Marilyn added code tags)
[ January 01, 2004: Message edited by: Marilyn de Queiroz ]

[Barry Gaunt]

If your problem boils down to permuting a list of strings then I suggest that you take a look at java.util.Collections. There is a shuffle method that does just that. You will also find java.util.Arrays useful to get yourself a List to shuffle.
[ January 02, 2004: Message edited by: Barry Gaunt ]

[Marilyn de Queiroz]

Originally posted by pt wee:
I use random method, sometime same question appear on the applet.
Try using shuffling method but don't know how to do.

Random will be random, sometimes the same question will appear more than once. You may need to "delete" those questions after they are "used" to prevent them from reappearing, or flag them as "used".