现有: 1. class Propeller2 { 2. pulolic static void main (String[]args)//add code here? 3. { new Propeller2().topGo(); } 4. 5.void topGo() //add code here? 6. { middleGo(); } 7. 8.void middleGo() //add code here? 9. { go(); 10. System.out.println ("late middle"); } 11. void go() //add code here? 12. {throw new Exception(); } 13. } 为使代码通过编译,需要在哪一行加入声明throws Exception?