Java Certification Question 0102

Which of the following statements about threading are true?

1) You can only obtain a mutually exclusive lock on methods in a class that extends Thread or implements runnable
2) You can obtain a mutually exclusive lock on any object
3) A thread can obtain a mutually exclusive lock on a method declared with the keyword synchronized
4) Thread scheduling algorithms are platform dependent

Answer :

1) b=m;
3) d =i;

You can assign up the inheritance tree from a child to a parent but not the other way without an explicit casting. A boolean can only ever be assigned a boolean value.