对下列现象的形成,判断正确的是( )
A:冬天窗户上的水雾凝结在窗户的外侧
B:潮湿的夏天,从冰箱里拿出的啤酒瓶会“出汗',这是汽化现象
C:加碘食盐开袋后一段时间,碘含量减少,这是升华现象
D:霜和雪的形成都是凝固现象
—________ will you ask for help when you get into trouble?
—My parents, I think.
下列实际应用中,主要从密度的角度考虑的是( )
You had better _________ wine because you have to drive back home.