A:沸点:PH3<NH3<H2O
B:碱性:Ba(OH)2<Ca(OH)2<KOH
C:熔点:MgBr2<SiCl4<BN
D:酸性:H2CO3<HClO<HNO3
下列省区中,从东向西自然景观出现明显“草原—草原荒漠—荒漠”变化的是 ( )
Each of us has _________ life goals, which will guide us to a bright future. Without life goals, we may waste our lifetime.