钨极氩弧焊焊不锈钢时电源种类和极性应采用()。
A. 交流方波电源
B. 交流电源
C. 直流正接
D. 直流反接
可以先解开他的衣领，让他侧卧，然后打电话叫救护车
A. The security may open his coat, let him lie on his side and ring the bell
B. The security may lock his collar, let him lie on his side and ask for help
C. The security should let him lie on his side while unlocking his clothes and waiting for the ambulance
D. The security may unlock his collar, let him lie on his side and call an ambulance
The officer has made a security plan for the performance
A. 这位安全官已经制定了演出方案
B. 这位安全官已经制定了预案
C. 这位安全官已经制定了演出安保方案
D. 这位先生已经制定了安全生产方案
We’ll immediately organize our securities to disperse the traffic and crowds
A. 我们马上命令保安疏散车辆和人群
B. 我们尽量组织保安疏散车辆和人群
C. 我们马上召集保安疏散车辆和人群
D. 我们马上组织保安疏散车辆和人群
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