A program uses the following string:
   String s = "CS2000";
Assuming the following all compile, which of these, when executed, will return the integer 2?

(a) s.indexOf("S");
(b) s.indexOf("2");
(c) s.substring(2, 3);
(d) s.substring(3, 4);
(e) s.substring(0, 2).length();

Select all correct answers.