如图所示,一杯果汁(ρ果汁>ρ水)中浮着一些冰块,如果冰全部熔化后,液面将( )
A:上升
B:不变
C:下降
D:无法确定
根据图示回答下列问题:
引发图中所示人口流动的最主要的因素是( )
My sister ______ goes to bed early because she needs a lot of sleep every day.