1. (20 pts) what is the output of this code sequence? b b1 = new b(); 2. (20 pts) what is the output of this code sequence? b b3 = new b(); int n = b3.foo2(); 3. (20 pts) what is the output of the following code? //b4 is a b object reference system. out. println(b4.; 4. (40 pts) you coded the following class: public class n extends string, integer { } when you compile, you get the following message: n. java: 1: ‘{‘ expected public class n extends string, integer ^ 1 error explain what the problem is and how to fix it.