A:①②
B:②③
C:②④
D:③④
用括号内所给单词的适当形式填空,(1)All those foreign____ (thief) have been caught.(2) Is Australia the____ (three) largest island country in the world?(3)Look, our dog Eddie is lying____ (comfort) on the grass.(4)There are a lot of differences between John and____ (I)(5)Our____ (know) of the universe is growing all the time.
138÷7≈____ 298÷5≈____ 274÷9≈____
在如图所示电路中,电源内阻不可忽略。开始时电键K1、K2均闭合,现先断开电键K1,则电压表与电流表的示数均发生变化,设它们的示数变化量之比为M1=DU1/DI1,再断开电键K2,两表新的示数变化量之比为M2=DU2/DI2,若已知R2<R3,则比较M1与M2的绝对值的大小应有 ( )