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public class NamedCounter { 
private final String name； 
private int count； 
public NamedCounter（String name） { this.name = name； } 
public String getName（） { return name； } 
public void increment（） { coount++； } 
public int getCount（） { return count； }
public void reset（） { count = 0； } } 
Which three changes should be made to adapt this class to be used safely by multiple threads？ （）

public class TwoThreads { 
private static Object resource = new Object（）； 
private static void delay（long n） { 
try { Thread.sleep（n）； } 
catch （Exception e） { System.out.print（”Error “）； } 
} 
public static void main（String[] args） { 
System.out.print（”StartMain “）； 
new Thread1（）.start（）； 
delay（1000）； 
Thread t2 = new Thread2（）； 
t2.start（）； 
delay（1000）； 
t2.interrupt 
delay（1000）； 
System.out.print（”EndMain “）； 
} 
static class Thread 1 extends Thread { 
public void run（） { 
synchronized （resource） { 
System.out.print（”Startl “）； 
delay（6000）； 
System.out.print（”End1 “）； 
} 
} 
} 
static class Thread2 extends Thread { 
public void run（） { 
synchronized （resource） { 
System.out.print（”Start2 “）； 
delay（2000）； 
System.out.print（”End2 “）； 
} 
} 
} 
} 
Assume that sleep（n） executes in exactly m milliseconds， and all other code executes in an insignificant amount of time. What is the output if the main（） method is run？（）