下面2个类, 你想在第二个类里面启动第一个类的线程，在第15行应该怎样做？（ ）
1 public class Century implements Runnable {
2 public void run () {
3 for (int year = 1900;year < 2000;year++) {
4 System.out.println(year);
5 try {Thread.sleep(1000);
6 } catch(InterruptedException e) {}
7 }
8 System.out.println("Happy new millenium!");
9 }
10 }
11
12 class CountUp {
13 public static void main (String [] args) {
14 Century ourCentury = new Century();
15
16 }
17 } 
