高温巴氏消毒效果好，但不能杀灭（）
A.繁殖型微生物
B.大肠杆菌
C.芽孢型微生物
D.沙门菌
E.酵母菌
参考答案：C
________ you met the foreigner from Canada?
A. Where it was that B Who it was that
C. Where was it that D. Where was that
是指对周期交流电进行付立叶‘级数分解，得到频率为基波大于( )整数倍的分量。
A．2
B．1
C．2
D．0.5
