A. 2,3,1,6,8,7,5,4,10,9, B. 3,4,2,7,9,8,6,5,11,10, C. 2,4,3,9,12,12,11,11,18,9, D. 1,2,3,6,8,7,5,4,10,9,
A. 10,One*Dream! B. 9,One*Dream! C. 9,One*World D. 10,One*World
A. 0 B. -20 C. -10 D. 10
A. 并 B. 自然连接 C. 笛卡尔积 D. 交