简答题 翻译：Proper control is vital and must be established.

问答题翻译：The most widely used indicator of a crude oil's worth to the producer is its API (American Petroleum Institute) gravity.

问答题翻译：The operation of a gas transmission system that moves gas over a large geographic area and contains several compressor stations and other facilities is a complex control challenge.

问答题翻译：The success of nontechnical methods averages 4.4% or about one third as success as technical methods.

问答题翻译：They are built on the same principle as the supertankers the wall of ship is also the wall of the oil tanks.

问答题翻译：Of primary importance is the fact that the prognosis represents a firm commitment as to drilling engineers ultimate responsibility.