交叉弹性为（）时，说明X价格的变动于产品Y需求量的变动方向一致。
A、大于零
B、小于零
C、等于零
D、不一定
参考答案：A
There ______ quantities of apples in the basket and there was ______ milk in the bucket. [ ]
A. were; a number of
B. was; quantities of
C. were; a quantity of
D. was; a good many
肾阳虚，命门火衰之病证，为阴寒弥漫，元阳不振。治疗宜( )
A．补益肾气
B．调补阴阳
C．温补肾阳，补益命火
D．滋肾益阴，阴得阳化
E．温肾助阳，化气行水
