Answer the following statements true (T) or false (F)

1. When an interface lists a method as “optional,” you do not need to implement it when defining a
class that implements the interface.
2. For-each loops can not be used with Collection classes.
3. Elements of a vector must be of a primitive type, such as int, double, or char.
4. The AbstractSequentialList class provides efficient implementation of sequentially moving through
the list at the expense of having inefficient implementation of random access to elements.

1. False
2. False
3. False
4. True