某电炉电阻丝电阻为10Ω,接在电压为220V的电源上,其功率为()W。
A. 2200
B. 4840
C. 9680
D. 2420
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精馏塔顶得到的是CO2和()CO2的轻组分,塔釜得到的是沸点()二氧化碳的重组分
Regulations require certain records to be retained on board for at least 3 months after a ship is involved in a casualty or until advised that they are no longer needed on board by the ().
A. owner
B. Master
C. person in charge
D. Officer in Charge,Marine Inspectio
任何人通过培训后,只要会使用防突钻机,就可以担任防治煤与瓦斯突出工作。()
A. 正确
B. 错误