Which one is a valid declaration of a boolean?

Which one is a valid declaration of a boolean?

2) Which of these values can a boolean variable contain?

3) Which of these can not be used for a variable name in Java?

4) What is the output for the below code ?

 public class Test
 { 
       public static void main(String[] args)
 { 
             byte b = 6; 
             b+=8;
             System.out.println(b);
             b = b+7;
             System.out.println(b); 
       } 
 }

5) Which of these occupy first 0 to 127 in Unicode character set used for characters in Java?