交联聚乙烯电缆外护套和接头外护套的直流耐压值为（）。
A.6kV
B.10kV
C.25kV
D.35kV
参考答案：B
国家实行（）和（）分级粮食储备制度。
It is playing computer games he spends so much time that he fails all the exams
A．which
B．what
C．in which
D．that
