二萜分子中异戊二烯数目是
A.2个
B.3个
C.4个
D.5个
E.6个
参考答案:C
解析:由2个异戊二烯单元组成的化合物称单萜,二萜则有4个异戊二烯单元。
Either you or one of your students _______ to attend the meeting that is due tomorrow.
A.are
B.is
C.have
D.be
下列哪一个不属于从众的原因( )
A.合法权利
B.行为参照
C.群体的凝聚力
D.对偏离的恐惧