A.Cat
B.Dog
C.Compilation fails.
D.The code runs with no output.
E.An exception is thrown at runtime.

A.The Thread.sleep（） method can take t1 as an argument.
B.The Object.notify（） method can take t1 as an argument.
C.The Thread.yield（） method can take t1 as an argument.
D.The Thread.setPriority（） method can take t1 as an argument.
E.The Object.notify（） method arbitrarily chooses which thread to notify.

A.move the line 12 print statement into the foo（） method
B.change line 7 to public synchronized void go（）{
C.change the variable declaration on line 2 to private volatile int x；
D.wrap the code inside the foo（） method with a synchronized（this） block
E.wrap the for loop code inside the go（） method with a synchronized block synchronized（this）{//for loop code here}

A.private synchronized Object o；
B.void go（）{   synchronized（）{/* code here */}
C.public synchronized void go（）{/* code here */}
D.private synchronized（this） void go（）{/* code here */}
E.void go（）{   synchronized（Object.class）{/* code here */}
F.void go（）{   Object o = new Object（）；   synchronized（o）{/* code here */}

A.Compilation fails.
B.An exception is thrown at runtime.
C.The code executes and prints "StartedComplete".
D.The code executes and prints "StartedComplete0123".
E.The code executes and prints "Started0123Complete".

A.It is possible to synchronize static methods.
B.When a thread has yielded as a result of yield（）， it releases its locks.
C.When a thread is sleeping as a result of sleep（）， it releases its locks.
D.The Object.wait（） method can be invoked only from a synchronized context.
E.The Thread.sleep（） method can be invoked only from a synchronized context.
F.When the thread scheduler receives a notify（） request， and notifies a thread， that thread immediately releases its lock.

A.Compilation fails.
B.An exception is thrown at runtime.
C.The code executes normally and prints "foo"；
D.The code executes normally， but nothing is printed.

A.The output could be 5-1，6-1，6-2，5-2
B.The output could be 6-1，6-2，5-1，5-2
C.The output could be 6-1，5-2，6-2，5-1
D.The output could be 6-1，6-2，5-1，7-1

A.4
B.5
C.8
D.9
E.Compilation fails.
F.An exception is thrown at runhime.
G.It is impossible to determine for certain.

A.This code can throw an InterruptedException.
B.This code can throw an IllegalMonitorStateException.
C.This code can throw a TimeoutException after ten minutes.
D.Reversing the order of obj.wait（） and obj.notify（） might cause this method to complete normally.
E.A call to notify（） or notifyAll（） from another thread might cause this method to complete normally.
F.This code does NOT compile unless "obj.wait（）" is replaced with "（（Thread） obj）.wait（）".

A.java.lang.RuntimeException： Problem
B.run.java.lang.RuntimeException： Problem
C.End of method.java.lang.RuntimeException： Problem
D.End of method.run.java.lang.RuntimeException： Problem
E.run.java.lang.RuntimeException： Problem.End of method.