已知α,β表示两个不同的平面,m为平面α内的一条直线,则“m⊥β”是“a⊥β”的[ ]
A.充分不必要条件
B.必要不充分条件
C.充要条件
D.既不充分也不必要条件
答案:A
一批运动服装,原价每套m元,现按原价的八折出售,则每套售价为______元;若原价每套45元,则打折后每套售价为______元.
Kate looked so sad at the news that she failed in the exam that I didn't know what to say to ____ her. [ ]
A. treat
B. interest
C. comfort
D. annoy