4. (4) Negate the following quantified statements: a. All alligators are black b. Some athletes are professional players 5. (6) Let B(x) be "x is a bird", Fr) be "x has feathers" and YCr) be "x can fly". a. Translate into a formula using quantifiers: All things with feathers are birds. b. Translate into a formula using quantifiers: Some things with feathers cannot fly. 6(6) Prove that for all sets A and B, (A-B')-(A B) using a set-membership table