11.rbo = new ReallyBigObject（）；
12.//more code here
13.rbo = null；
14./*insert code here*/
Which statement should be placed at line 14 to suggest that the virtual machine expend effort toward recycling the memory used by the objectrbo？（）

package test；
class Target{
public String name="hello"；
}
What can directly access and change the value of the variable name？（）

Given a class Repetition：
1.package utils；
2.
3.public class Repetition{
4.public static String twice（Strings）{returns+s；}
5.}
and given another class Demo：
1.//insert code here2.
3.public class Demo{
4.public static void main（String[]args）{
5.System.out.println（twice（"pizza"））；
6.}
7.}
Which code should be inserted at line 1 of Demo.java to compile and run Demo to print“pizzapizza”？（）

Given classes defined in two different files：
1.package util；
2.public class BitUtils{
3.private static void process（byte[]b）{}
4.}
1.package app；
2.public class SomeApp{
3.public static void main（String[]args）{
4.byte[]bytes=newbyte[256]；
5.//insert code here
6.}
7.}
What is required at line 5 in class SomeApp to use the process method of BitUtils？（）