A vessel not under command shall display().
A. two red lights at night and two black balls during daylight
B. two red lights at night and three black balls during daylight
C. three red lights at night and two black balls during daylight
D. three red lights at night and three black balls during daylight
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计算题:检定一只测量范围为0-10MPa,准确度为1.5级的弹簧管式压力表,所用的精密压力表的量程和准确度等级应为多少?