This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
For the first ques. if you make y= null then any .operator will result in exception so that could be the answer.
I don't know if it is true or not. But I guessed the ans for 2nd to be "e". There won't be runtime or compile error as char can be added to String. I know last two comparisons are false and I assumed the final constant should evaluate to true on ==. So I chose "e"