1. (20 pts) Given the following code: public static void foo3(String s) { if (s.length() >0) { System.out.print(s.charAt(s.length() -1)); foo3(s.substring(0, s.length() -1)); } } What is the output of: foo3();

2. (20 pts) Using the code in #1, What is the output of foo3(Hi)?

3. (20 pts) Fill in the missing code: This recursive method returns even if the length of a give String is even, and odd if the length of the String is odd. public static String foo(String s) { if (s.length() ==0) return even; else if (s.length() = = 1) return odd; else //your code goes here }

4. (40 pts) You coded the following in the file Test.java : System.out.println( foo(5)); //more code here public static int foo(int n) //line 9 { if (n = = 0) return 1; else System.out.println(n* foo(n-1) ); } //line 15 At compile time, you get the following error: Text.java: 15: missing return statement } //line 15 ^ 1 error Explain what the problem is and how to fix it.