问题
单项选择题
Records which must be retained on board after report of casualty to a vessel include the（）.
A.tour reports
B.hull reports
C.machinery repair record book
D.deck equipment log
答案
参考答案：A
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mm，假设1个时间单位相当于现在的0.5s。由此可以推测实验时光滑斜面的长度至少为____________m，斜面的倾角约为____________度。（g取10m/s2） 