治头痛无论风寒、风热、风湿、血瘀、血虚均可选用的药是（）
A.川芎
B.白芷
C.菊花
D.羌活
E.熟地
参考答案：A
计算cos60°=______．
Tom was over there. His red clothes stood out clearly _____the snow.
A．behind
B．for
C．against
D．beyond
