.We should give a hand to the people ________ need help.
A.who
B.whose
C.whom
D.when
答案:A
干式系统适用于环境温度低于()或高于70℃的场所。
(A)25
(B)7
(C)4
(D)0
为客户提供办理用电手续属于什么类型的服务?