In ship construction，keel scantlings should be the greatest（）.

The bypass valve on a self-contained breathing device should be opened if（）.

An example of a messenger is a（）.

The rudders are amidships and both screws are going ahead. What will happen if the starboard screw is stopped?（）

The connected joints of pipe，usually made of three joints of pipe approximately 90 feet long，racked in the derrick when making a trip are called a（）.

Limit switches are used on which davits?（）

An example of a modern anchor which has a stock is a(n)（）.

The boat is stowed on the davit rather than on a cradle with which type of davit?（）

The exhaust pipe must be gas tight throughout its entire length otherwise（）.

The C02 flooding system is actuated by a sequence of steps which are（）.