In a centrifugal Freon refrigeration system, the overall capacity of the system is increased by（）
A. opening more bypass lines
B. opening additional expansion valves
C. adding refrigerant
D. speeding up the machine
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You are on watch and the pilot has just anchored the vessel.The next thing that you should do after the anchor has been let go is to（）.
A. Stop the engines
B. Escort the pilot to the accommodation ladder
C. Plot the vessel's position on the chart
D. Make a round of the weather deck
数字证书载体是指能够装载电子证书的特殊物理介质，网上银行专业版用户必须使用（）
保险产品是具有法律效应的合同，具有（）的特点，一旦签订保险合同，不能随意更改。
A. 长期性
B. 持续性
C. 永久性
D. 暂时性
智能电源屏可以实现电源屏实时数据显示，包括（）信息、开关量信息和实时报警信息。
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