1. Explain what modifications would be needed to make the parenthesis matching algorithm check expressions with more kinds of parentheses such as 2. Complete the body of this method. You do not need to check the precondition. You may use the CharStack class. public static boolean balanced(String p) // Precondition: Each character of p is '(', ")', ' or'' // Postcondition: The method returns true if the characters form a // sequence of correctly balanced parentheses with each matching // a)' and each matching a Note that a sequence such as I (tJ is NOT balanced because when we draw lines to match the // parentheses to their partners, the lines cross each other. On the // other hand, ) and are both balanced 3. I am going to cxccute this code with TIIREE pushes and ONE pop IntStack s new IntStack( ); s.push(1); s.push (2); s.push(3); System.out.println(s.pop()); Suppose that s is represented by a partially filled array. Draw the state of the private instance variables of s after the above code manyItems data 4. I am going to execute this code with THREE pushes and ONE pop IntStack s new IntStack( s.push (1); s. push (2); s.push (3); System.out.println(s.pop()); Suppose that s is represented by a linked list. Draw the state of the private member variables of s after the above code