焊接机械机体必须使用单独导线接地,接地电阻不得大于()Ω。
A.4
B.10
C.15
D.20
参考答案:B
新型隐球菌脑膜炎的临床表现是什么?
汉译英:“有效期限;签发日期;运输方式”,正确的翻译为:()。
A.valid period;date of dispatch; means of transport
B.departure time; issuing date; means of conveyance
C.departure time; date of dispatch; means of conveyance
D.valid period; issuing date;means of transport