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class Computation extends Thread { 
private int num； 
private boolean isComplete； 
private int result； 
public Computation（int num） { this.num = num； } 
public synchronized void run（） { 
result = num * 2； 
isComplete = true； 
notify（）； 
} 
public synchronized int getResult（） { 
while （!isComplete） { 
try { 
wait（）； 
} catch （InterruptedException e） { } 
} 
return result； 
} 
public static void main（String[] args） { 
Computation[] computations = new Computation [4]； 
for （int i = 0； i < computations.length； i++） { 
computations[i] = new Computation（i）； 
computations[i] .start（）； 
} 
for （Computation c ： computations） 
System.out.print（c.getResult（） +“ “）； 
} 
} 
What is the result？（） 

public class Transfers { 
public static void main（String[] args） throws Exception { 
Record r1 = new Record（）； 
Record r2 = new Record（）； 
doTransfer（r1， r2， 5）； 
doTransfer（r2， r1， 2）； 
doTransfer（r1， r2， 1）； 
// print the result 
System.out.println（”rl = “ + r1.get（） +“， r2=” + r2.get（））； 
} 
private static void doTransfer（ 
final Record a， final Record b， final int amount） { 
Thread t = new Thread（） { 
public void run（） { 
new Clerk（）.transfer（a， b， amount）； 
} 
}； 
t.start（）； 
} 
} 
class Clerk { 
public synchronized void transfer（Record a， Record b， int amount）{ 
synchronized （a） { 
synchronized （b） { 
a.add（-amount）； 
b.add（amount）； 
} 
} 
} 
} 
class Record { 
int num=10； 
public int get（） { return num； } 
public void add（int n） { num = num + n； } 
} 
If Transfers.main（） is run， which three are true？（）