火灾自动报警系统中,明敷设各类管路和线槽时,应采用单独的卡具吊装或支撑物固定。吊装线槽或管路的吊杆直径不应小于()。
A、6mm
B、8mm
C、10mm
D、12mm
参考答案:A
The young boy is good _____ me. He is good _____ playing basketball.
He often tells me that it is good _____ my health to do more exercise. [ ]
A. at; to; for
B. to; at; for
C. at; for; in
D. to; in; for
机车车辆等技术设备须有()统一规定的标记。
A.铁路局
B.铁道部
C.国家