5. Let A = {1, 2, 3, 4} and R = {(1,1), (1,2), (2,1), (2,2), (3,4), (4,1), (4,4) }. (a) (4 points) Is R a reflexive relation? Why or why not? (b) (4 points) Is R a transitive relation? Why or why not? (c) (2 points) Represent this relation with a matrix or a digraph