题目

经过测算，地球的平均半径为 () A . 6357千米 B . 6371千米 C . 6378千米 D . 约4万千米 答案：BA computer cannot remember who_________；it simply does what __________. [　　] A．will use it; it was told B．uses it; it has told C．has used it; it was told D．has used it; it told