This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
SOme of the questions require you to know which class is a class and which is an interface and which classes implement those interfaces etc. Which methods belong to which interfaces so you know which Collection has the add method to add items and which has put method to add items.
So what you have in the K&B Book is what is on the exam about Collections.