单项选择题 The officer in charge of the engineering watch shall ensure that all machinery involved with the maneuvering of the ship can immediately be placed in the （） of operation when notified that the ship is in congested waters.

单项选择题 Texture measurement by instruments will give a value in degree. CelciusThis scale of measurement is normally used for all readings and temperature values （） dealing with theoretical calculations involving the gas laws.

单项选择题 （） thrust and resistance equal each other, the ship always travels at a constant speed.