下列各组物质的晶体中,化学键类型相同,熔化时所克服的作用力也相同的是( )
A.SO3 和SiO2
B.NaCl 和HCl
C.(NH4)2CO3和CH4
D.CO2和H2S
答案:D
— What kind of movies do you like?
— I like the movies ____ are about Chinese history.
A.who
B.whom
C.whose
D.that
输电架空线路巡视周期制定可以实现哪些功能?