answer 30)

1,2,3

public, private, static are all legal access modifiers for this inner class.

answer 31)

3) output of first0, first1, second0, second1

note that this code overrides and calls the start method. if you wished to get the output mixed you would need to override the run method but call the start method.

answer 32) 

2) setlayout(new gridlayout(2,2));
 

changing the layout manager is the same for an applet or an application. answer 1 is wrong though it might have been a reasonable name for the designers to choose. answers 3 and 4 are incorrect because changing the layout manager always requires an instance of one of the layout managers and these are bogus methods.

instead of creating the anonymous instance of the layout manager as in option 2 you can also create a named instance and pass that as a parameter. this is often what automatic code generators such as borland/inprise jbuilder do.

answer 33)

3) the code will cause an error at compile time

the error is caused because run should have a void not an int return type.

any class that is implements an interface must create a method to match all of the methods in the interface. the runnable interface has one method called run that has a void return type.the sun compiler gives the error

method redefined with different return type: int run() was defined as void run();
 

answer 34)

3) compilation and output of 0 followed by 1

the creation of an anonymous class as a parameter to go is fairly strange as you would expect it to override a method in its parent class (turing). you don't have to though. the fact that class turing extends thread means the anonymous instance that is passed to go has a start method which then calls the run method.