A class games.cards.Poker is correctly defined in the jar file Poker.jar. 
A user wants to execute the main method of Poker on a UNIX system using the command： 
java games.cards.Poker 
What allows the user to do this？（） 

1. public class GC { 
2. private Object o； 
3. private void doSomethingElse（Object obj） { o = obj； } 
4. public void doSomething（） { 
5. Object o = new Object（）； 
6. doSomethingElse（o）； 
7. o = new Object（）； 
8. doSomethingElse（null）； 
9.o=null； 
10. } 
11. } 
When the doSomething method is called， after which line does the Object created in line 5 become available for garbage collection？（） 

11. class Snoochy { 
12. Boochybooch； 
13. public Snoochy（） { booch = new Boochy（this）； } 
14. } 
15. 
16. class Boochy { 
17. Snoochy snooch； 
18. public Boochy（Snoochy s） { snooch = s； } 
19. } 
And the statements： 
21. public static void main（String[] args） { 
22. Snoochy snoog = new Snoochy（）； 
23. snoog = null； 
24. // more code here 
25. } 
Which statement is true about the objects referenced by snoog， snooch， and booch immediately after line 23 executes？（） 

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 object rbo？（） 

11. public void genNumbers（） { 
12. ArrayList numbers = new ArrayList（）； 
13. for （int i=0； i<10； i++） { 
14. int value = i * （（int） Math.random（））； 
15. Integer intObj = new Integer（value）； 
16. numbers.add（intObj）； 
17. } 
18. System.out.println（numbers）； 
19. } 
Which line of code marks the earliest point that an object referenced by intObj becomes a candidate for garbage collection？（） 

class Foo { 
private int x； 
publicFoo（intx） {this.x=x； } 
public void setX（ int x） { this.x = x； } 
public int getX（） { return x； } 
}  
public class Gamma { 
static Foo fooBar（ Foo foo） { 
foo = new Foo（ 100）； 
return foo； 
} 
public static void main（ String[] args） { 
Foo foo = new Foo（ 300）； 
System.out.print（ foo.getX（） + “-“）； 
Foo fooFoo = fooBar（ foo）； 
System.out.print（ foo.getX（） + “-“）； 
System.out.print（ fooFoo.getX（） + “-“）； 
foo = fooBar（ fooFoo）； 
System.out.print（ foo.getX（） + “-“）； 
System.out.prmt（ fooFoo.getX（））； 
} 
} 
What is the output of this program？（）

10. class Inner { 
11. private int x； 
12. public void setX（ int x） { this.x = x； } 
13. public int getX（） { return x； } 
14. } 
15. 
16. class Outer { 
17. private Inner y； 
18. public void setY（ Inner y） { this.y = y； } 
19. public Inner getY（） { return y； } 
20. } 
21. 
22. public class Gamma { 
23. public static void main（ String[] args） {
24. Outer o = new Outer（）；
25. Inner i = new Inner（）； 
26.int n=10； 
27. i.setX（n）； 
28. o.setY（i）； 
29. // insert code here 
30. System.out.println（ o.getY（）.getX（））； 
31. } 
32. } 
Which three code fragments， added individually at line 29， produce the output 100？（）

public class ItemTest { 
private final mt id； 
public ItemTest（int id） { this.id = id； } 
public void updateId（int newId） { id = newId； } 
public static void main（String[] args） { 
ItemTest fa = new ItemTest（42）； 
fa.updateId（69）； 
System.out.println（fa.id）； 
} 
} 
What is the result？（） 

public class Item { 
private String desc； 
public String getDescription（） { return desc； } 
public void setDescription（String d） { desc = d； }
public static void modifyDesc（Item item， String desc） { 
item = new Item（）； 
item.setDescription（desc）； 
} 
public static void main（String[] args） { 
Item it = new Item（）； 
it.setDescription（”Gobstopper”）； 
Item it2 = new Item（）； 
it2.setDescription（”Fizzylifting”）； 
modifyDesc（it， “Scrumdiddlyumptious”）； 
System.out.println（it.getDescription（））； 
System.out.println（it2.getDescription（））； 
} 
} 
What is the outcome of the code？ （）

11. class Payload { 
12. private int weight； 
13. public Payload（int wt） { weight = wt； } 
13. public void setWeight（mt w） { weight = w； } 
15. public String toString { return Integer.toString（weight）； } 
16. } 
17. 
18. public class TestPayload { 
19. static void changePayload（Payload p） {
20. /* insert code here */
21. } 
22. 
23. public static void main（String[] args） { 
24. Payload p = new Payload（）； 
25. p.setWeight（1024）； 
26. changePayload（p）； 
27. System.out.println（”The value of p is “+ p）； 
28. } 
29. } 
Which statement， placed at line 20， causes the code to print “The value of p is 420.”？（）