Question 2 Ceiling and floor functions (8 points) 1. Please draw the function graph of f(x) = [x/2] - [x/3] for x E [0, 6]. 2. Please draw the function graph of S(a) = [2x] + [x/2] for a e [-4, 4].Question 3 Congruence (6 points) If a =b (mod m), c= d (mod m), e = f (mod m), then prove a * c * e = b * d * f (mod m)