煤气作业的照明应在()m以外使用投光器。
A.5
B.10
C.20
D.15
参考答案:B
— Mr. White ?
— He comes from Canada. [ ]
A. Where is ; come
B. Where is; come from
C. Where does; from
D. Where does; come from
Access数据库包括表、查询、窗体、报表、 【8】 、宏和模块等基本对象。