Which method should be used to warm up the pump turbines prior to discharge（）.

On no account（）to be exceeded.

How should you signal the crane operator to lower the boom and raise the load（）.

Which operation may cause the pressure in an inert tank to fall below the prescribed limits（）.

If an attempt is made to hoist a load that exceeds the capacity of an electric winch，an overload safety device causes a circuit breaker to cut off the current to the winch motor（）.

Official draft measurements should be（）by authorized persons，agreed by both parties involved.

Which part provides for transverse control and positioning of a boom in a conventional yard and stay system（）.

When using slings，cargo handlers should take all the following precautions except（）.

What is/are the advantage（s）of cranes over conventional cargo booms（）.

Running an electric winch at slow speed over a long period of time causes（）.