下述四种物质的酸性强弱顺序是()
Ⅲ)pKa=4.2(Ⅳ)pKa=8.3
A.Ⅰ>Ⅱ>Ⅲ>Ⅳ
B.Ⅱ>Ⅳ>Ⅲ>Ⅰ
C.Ⅰ>Ⅲ>Ⅳ>Ⅱ
D.Ⅰ>Ⅱ>Ⅳ>Ⅲ
E.Ⅱ>Ⅲ>Ⅰ>Ⅳ
参考答案:C
Donkeys and camels are still widely used in some parts of the world as beasts of______.
A.cargo
B.freight
C.burden
D.lading
任何进入()的人员均应当按照规定更衣。