How to properly ask passengers to turn off mobile phone for take-off?
A. Could you please switch off your cell phone?
B. Would you please turn off your mobile phone?
C. Smoking is not allowed.
D. Remote-controlled equipment is prohibited.
What devices are not permitted to use for take-off and landing?
A. mobile phone
B. radios
C. laptop computer
D. remote-controlled equipment
飞机起飞时可以使用充电宝给手机充电。
A. 对
B. 错
要实现零、部件的互换性，除了合理地规定（）以外，还必须正确地进行（）和（），只有检测合格的零件，才能满足产品的（），保证其互换性能。
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