炉给水压力值最大16兆帕。最小15兆帕.试问应选用多大量程的压力表?
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人民币纸币票面裂口2处以上,长度每处超过()毫米以上的不宜流通。
A. 3
B. 4
C. 5
D. 6
维生素B2的化学名称为()。
A. 生育酚
B. 硫胺素
C. 核黄素
D. 视黄醇
()can be regarded as a vessel restricted in her ability to maneuver.
Any aircraft designed to maneuver on the water
B. A vessel engaged in dredging,surveying or underwater operations
C. A vessel under sail provided that propelling machinery is not used
D. A small vessel sailing at night