A:12π
B:323 π
C:4 3 π
D:4π3
下列有关名著内容的表述,不正确的两项是( )
We should try to help the ____________ because they have an illness which makes it difficult for them to move around.
图甲是某同学设计的调光电路图,他将粗细均匀的电阻丝R通过滑片P接入电路,闭合开关,滑片从最左端向最右端滑动的过程中,电压表与电流表的示数呈图乙所示的规律变化.(小灯泡的电阻不随灯丝温度的变化而改变)求:
下列对环境污染的认识中,正确的是( )