Use Algorithm 1 to find the transitive closures of these relations on 1, 2, 3, 4. a) (1, 2), (2,1), (2,3), (3,4), (4,1) b) (2, 1), (2,3), (3,1), (3,4), (4,1), (4, 3) c) (1, 2), (1,3), (1,4), (2,3), (2,4), (3, 4) d) (1, 1), (1,4), (2,1),(2,3), (3,1), (3, 2), (3,4), (4, 2) | Numerade