1. What is the output produced by the following?
   String test = "abcdefg"; System.out.println(test.substring(3,5));
2. What is the output produced by the following?
   String test = "abcdefg"; System.out.println(test.substring(3));
3. What is the output produced by the following?
   System.out.println("abc def");
4. What is the output produced by the following?
   System.out.println("abc\ def");