差别感觉阈限越小表明差别感受性越( )。
A．高B．低C．弱D．小
参考答案：A
I'm afraid I can't attend your wedding ceremony, but thanks for the invitation _______. [ ]
A. personally
B. briefly
C. anyway
D. afterwards
具有临界胶束浓度是哪项的特性（）
A.溶液
B.胶体溶液
C.表面活性剂
D.高分子溶液
E.亲水胶
