问答题
设Ω={1,2,3,4,5,6,7,8,9,10};A={1,2,3,4};B={1,3,5,7,9};C={5,6,7,8} 求(1)AB;(2)A∪B;(3);(4);(5);(6)(A∪B)C;(7);(8)