[1 0 11 0 1 1 1 A) Let A = {1, 2, 3, 4, 5} and R a relations on A whose matrices is MR = 0 0 1 1 0 0 1. 1) Show that (A, R) is a poset (5 pts) 2) Find maximal, minimal, least and greatest if they exist (4 pts) B) Find the root and the height of (T, vo) where A = {1,2, 3, 4, 5, 6, 7} and T = {(1,4), (2, 3), (3, 1), (4, 5), (1,6), (4, 7)} (Show your work) (5 pts) C)Evaluate the expression which is given in post-order notation pts) 35 x 37 + 41+ (4