测量的四个要素是（）。 被测对象。 计量单位。 测量手段。 测量精度。
组合式开关电源系统由以下哪几部分组成（）。 交流配电单元。 整流模块。 监控模块。 直流配电单元。
农信银电子汇兑业务提交后需要换人复核，下列选项属于复核员录入内容的是（）。 接收行行号。 接收行行名。 费用收取方式。 缴费方式。
Care must be taken to condition the （）in the boiler to prevent scaling, and corrosion, which can weaken the pressure vessel. water。 fuel。 steam。 air。
A vessel proceeding along the course of a narrow channel shall keep as near to the outer limitof the channel which lies on her starboard side as it is safe and practicable.Which one of the followings does the statement express?（）. A vessel shall proceed near the other vessel on her starboard side on the narrow channel since it is safe and practicable。 A vessel shall avoid proceeding near the starboard outer limit of a narrow channel as long as it is safe and practicable。 A vessel shall avoid proceeding along the channel because it is not safe and practicable。 A vessel shall proceed near the starboard outer limit of a narrow channel to the degree in which it is safe and practicable。
价值类型主要有以下哪几种（）。
