In ship construction，frame spacing is（）.

The series of valves used to control the return flow in well control operations is called the（）.

On a ship，a door that is required to be marked KEEP CLOSED is designed to（）.

As oil pipe line connections were broken，（）quantity of oil was caused to spill onto the wharf and into the dock water.

Anchors are prevented from running out when secured by the（）.

Cargo pump relief valves are piped to the（）.

In relation to cargo gear，what does SWL mean?（）.

An integral part of a blowout preventer that serves as the closing element on an open hole，and whose ends do not fit around the drill pipe but seal against each other and shut off the space below completely is the（）.

Centrifugal pumps have what advantage(s) over reciprocating pumps?（）.

Each cylinder in a two stroke cycle engine experiences combustion（）.