A rocket burns propellant rapidly and most rockets carry a supply that last just a few sec

A variable pitch propeller is made _____ a boss with separate blades mounted into it.

You are on a single－screw vessel with a right－handed propeller，and you are making headway.

When the propeller blades are integral with the hub, the propeller is called a _____.A.bui

Propeller running at ____ are generally efficient.A.high speedsB.medium speedC.low speedsD

Which of the following statements about a rocket

.A rocket is pushed up into the air when.A.hot ga