单项选择题
A.150V B.200V C.250V D.300V
A.18℃-28℃,40%-65% B.21℃-25℃,40%-65% C.18℃-28℃,30%-75% D.21℃-25℃,30%-75%
A.尼龙 B.木头 C.硬橡胶 D.特氟龙