Tom is better than any other ______ in his class.
A:students
B:student
C:studnts
D:studentes
杨家将的故事讲述了“澶渊之盟”订立之前,我国哪两个政权之间的争战( )
如果一个式子与﹣3ab的积为﹣34a2bc,求这个式子.