格林模拟试题一（上）(5)

 question 16)

which of the following statements are true?

1) methods cannot be overriden to be more private
3) private methods cannot be overloaded
question 17)

what will happen if you attempt to compile and run the following code?

class base {}
class sub2 extends base {}
public static void main(string argv){
sub s=(sub) b;
}
1) compile and run without error 
3) runtime exception 

question 18)

which of the following statements are true?

1) system.out.println( -1 >>> 2);will output a result larger than 10
>> 2); will output a positive number 
> 1); will output the number 1 
4) system.out.println( 1