A mercurial barometer at sea is subject to rapid variations in height(”pumping”)due to the pitch and roll of the vessel.To avoid this error，measurements of atmospheric pressure at sea are usually measured with a(n)().

A flashing light is a light that ().

Allowances may be made for the expansion and contraction in piping by the use of expansion joints or ().

You see a vessel displaying three lights in a vertical line.The highest and lowest lights are red and the middle light is white.She is also showing a white light at the stern，which is lower than the forward light.It could be a ().

For optimum stability during jacking operations，mat ballast tanks or spud cans should be ().

A vessel will NOT show sidelights when ().

A mercurial barometer at sea is subject to rapid variations in height(”pumping”)due to the pitch and roll of the vessel.To avoid this error，measurements of atmospheric pressure at sea are usually measured with a(n)().

()is where the crew eat their meals.

If a davit-launched life raft aboard a vessel cannot be launched because of damage to the davit，you should ().

The term flood current refers to that time when the water ().

Fighting a fire in the galley poses the additional threat of ().