A.heavy rain within six hours B.a decrease in wind velocity C.a change in the present weather conditions D.that fog will soon set in
单项选择题A radar range to a small,charted object such as a light will provide a line of position in which form? ()
A.Straight line B.Arc C.Parabola D.Hyperbola
单项选择题A quick and rapid motion of a ship in a seaway is an indication of a(n) ().
A.large GM B.high center of gravity C.excessive free surface D.small GZ
单项选择题A pumproom is suspected of accumulating gases after a ventilation machinery breakdown. Where should the combustible gas indicator case be placed when testing the pumproom atmosphere for combustible gases? ()
A.In the lower level of the pumproom B.In the middle level of the pumproom C.In the upper level of the pumproom D.On the deck outside the pumproom
单项选择题A psychrometer has two thermometers that provide dry bulb and wet bulb temperatures. By comparing these two temperature readings with a set of tables you can determine the ().
A.atmospheric pressure B.wind speed C.relative humidity and dew point D.wind chill factor
单项选择题A predictable result of a vessel nearing a bank or edge of a channel is that the().
A.stern is drawn to the bank as the bow sheers off B.bow sheers toward the bank C.vessel continues in a straight line,but with greatly reduced maneuverability D.vessel will be drawn bodily into the bank unless the engines are stopped