Urgent

Q5. Let r and y be propositional variables. Which of the following propositions is not a tautology? A. T - I B. (x -+ y) V(y -+ x) C. -(x1 -1) D. y -+ (xV-x) E. x x F. (y A - y ) -+ 2 Q6. How many numbers, at a minimum, should we choose at random from S = {-4, -3, -2, -1, 1, 2, 3, 4} in order to guarantee that two of the numbers we have chosen have a sum equal to 0? A. 2 B. 3 C. 4 D. 5 E. 6 F. None of the above