A.a
B.b
C.c
D.ac
E.abc

A.test end
B.Compilation fails.
C.test runtime end
D.test exception end
E.A Throwable is thrown by main at runtime.

A.0.0
B.Compilation fails.
C.A ParseException is thrown by the parse method at runtime.
D.A NumberFormatException is thrown by the parse method at runtime.

A.Line 16
B.Line 17
C.Line 18
D.Line 19
E.The object is NOT a candidate for garbage collection.

A.harrier
B.shepherd
C.retriever
D.Compilation fails
E.retriever harrier
F.An exception is thrown at runtime

A.Line 5
B.Line 6
C.Line 7
D.Line 8
E.Line 9
F.Line 10

A.null
B.zero
C.some
D.Compilation fails.
E.An exception is thrown at runtime.

A.Foo.beta（） is a valid invocation of beta（）.
B.Foo.alpha（） is a valid invocation of alpha（）.
C.Method beta（） can directly call method alpha（）.
D.Method alpha（） can directly call method beta（）.

A.It is true that j==i.
B.It is false that j==i.
C.An exception is thrown at runtime.
D.Compilation fails because of an error in line 13.

A.System.load（"prop.custom"）；
B.System.getenv（"prop.custom"）；
C.System.property（"prop.custom）；
D.System.getProperty（"prop.custom"）；
E.System.getProperties（）.getProperty（"prop.custom"）；

A.6
B.7
C.10
D.11
E.Compilation fails.
F.An exception is thrown at runtime.