根据题干分析可得:1620=45=÷30=4:5.
故答案为:16;30;5.
甲、乙两导体的电阻之比为R1∶R2=1∶2,分别接在不同的电路中,测出通过它们的电流之比为4∶1,则在相同的时间内电流经过甲、乙两导体所做的功之比为[ ]
A.1∶2
B.4∶1
C.8∶1
D.1∶8
______your mother _____ TV every day?
A. Does; watches
B. Is; watching
C. Does; watch
D. Do; look