A.IT:null

B.A NullPointerExceptionis thrown at run time.

C.IT:0.0

D.A compilation error occurs.

A.

B.

C.

D.

A.Hello : Jim Hello : John Hello : Jeff

B.Jim John Jeff

C.The program prints nothing.

D.A compilation error occurs.

A.Stream.of(list1, list2).flatMapToInt(list -> list.stream()).forEach(s -> System.out.print(s + " "));

B.Stream.of(list1, list2).flatMap(list -> list.stream()).forEach(s -> System.out.print(s + " "));

C.list1.stream().flatMap(list2.stream().flatMap(e1 -> e1.stream()).forEach(s -> System.out.println(s + "
"));

D.Stream.of(list1, list2).flatMap(list -> list.intStream()).forEach(s -> System.out.print(s + " "));

A.Q

B.S

C.U

D.R

E.T

F.P