Every act of assistance or salvage，which has had a useful result，should give a right to （）remuneration.

You are underway and approaching a bend in the channel where vessels approaching from the opposite direction cannot be seen．You should sound（）.

What is a functional or carriage requirement for compulsory vessels?（）

What is a GMDSS functional or carriage requirement for compulsory vessels?（）

With the introduction of the electronic computer, there is no complicated problem _____ can be solved in a few hours.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

Vessels lying afloat at buoys for more than 24 hours should use anchor chain for（）and insurance wire for（）.

The nozzle of a gasoline hose or can should be kept（）.

During counterflooding to correct a severe list or trim aggravated by an off-center load，a ship suddenly takes a list or trim to the opposite side. You should（）.

If help has not arrived in 10-12 hours after you abandon a vessel in a survival craft，you should（）.

If help has not arrived in 10-12 hours after abandoning a vessel in a rescue boat，you should （）.

已知“A、B二人中至少有一人懂英语”、“只有B刁懂英语，A才懂英语”和“A不懂英语并且B也不懂英语”这三个判断中，只有一个为真。据此，便可必然推出下列判断中为真的是（）。