a. Show via formal proof that the expression((-Q~PAC(QAR)VQ)~P)) is logically equivalent to~P. Give a reason for each step of your proof and also provide the numbers of any previous steps being referred to. (4 marks) 1. a. Prove that at-b, a are enough to conclude b (2 marks) 2. a. Given the following quantified expression: Vz (P(z) Q(2) Y3y Q(y)-> R(z) i. Parenthesize the expression so it is explicit which operands go with which operands and so the scope of each quantifier is a parenthesized expression. (1 mark) i. For each occurrence of each variable, indicate if it is bound or free? (2 marks) Rename the variables so that distinct names are used for each distinct variable (1 mark) iii. Identify the free variable(s) in the following statements. If a variable appears more than once in the formula, be clear about which occurrence of the free variable you are referencing. a. .. ii p(x) ~r(y,a) (2 marks) 3x, r(x,y)) (2 marks)