Let X = {1,2,3,4}. Consider the following relation on X: R = {(1, 1), (2, 2), (3, 3), (4,4), (1, 2), (1, 4), (2, 1), (2, 4), (4,1)} (a) Is R reflexive? Explain your answer for credit. (b) Is R symmetric? Explain your answer for credit. (c) Is R transitive? Explain your answer for credit. (d) Construct a binary relation Son X that is reflexive, is symmetric, and is not transitive. Write your relation S as a set of ordered pairs.