数字万用表是功能强大的测量仪器，但它不能测量______。
A．电流 B．串扰 C．电压 D．电容
参考答案：B
The farm as well as its neighboring hills which we once spent so
much time ______ on a new look as recently as last year. [ ]
A. on has taken
B. has taken
C. on having taken
D. having taken
选择性阻断β1肾上腺素受体的药物有（）
A.阿替洛尔
B.乌拉地尔
C.拉贝洛尔
D.美托洛尔
E.艾司洛尔
