压缩空气管道可采用有缝钢管和无缝钢管,阀门一般采用闸阀。
参考答案:对
— Any fashion news about skirts?
— Yes. This season’s short skirts have gained popularity now, although they to be shocking at first.
A.have been thought
B.were thought
C.are thought
D.had thought
根据现行《火灾自动报警系统设计规范》,火灾自动报警系统中,消防通讯设备等的电源宜采用()供电
A.接地交流
B.UPS装置
C.照明电源
D.消防电源