We want to simulate multiple rocket launches by ACME Rocket Inc. Each launch has a countdown, like this

10...(delay)9...(delay)8...(delay)... 1...(delay)Liftoff

The initial counter value and the delay (in milliseconds) are variable.

Complete the following file:

CountdownRunnable.java

/** A runnable that prints a countdown. */ public class CountdownRunnable implements Runnable { /** Constructs the runnable object. @param startingValue the starting value of the countdown @param aDelay the delay between counts */ public CountdownRunnable(int startingValue, int aDelay) { counter = startingValue; delay = aDelay; } // your work here private int counter; private int delay; // this method is used to test your work public static void main(String[] args) { CountdownRunnable r1 = new CountdownRunnable(10, 10); CountdownRunnable r2 = new CountdownRunnable(20, 5); Thread t1 = new Thread(r1); Thread t2 = new Thread(r2); t1.start(); t2.start(); } }