目的在于考察候选方法的特异性的实验是()
A.重复性实验
B.回收实验
C.干扰实验
D.方法比较实验
E.预实验
参考答案:C
— Rooney used to ______ late for school.
— Yes, but now she is use to ______ up early. [ ]
A. be; get
B. being; getting
C. being; get
D. be; getting
在匀强磁场中,有一接有电容器的回路,如图10所示.已知C="30" μF,l1="5" cm,l2="8" cm,磁场以5×10-2 T/s的速度增强.则 ( )
图10
A.电容器上板带正电,带电荷量2×10-9 C
B.电容器上板带正电,带电荷量6×10-9 C
C.电容器上板带负电,带电荷量4×10-9 C
D.电容器上板带负电,带电荷量6×10-9 C