对口器分为（）对口器两种。 内、外。 轻、重。 直、弯。 长、短。
在正常使用条件下，最低保修期限为5年的工程是（）。 电气管线工程。 装修工程。 屋面防水工程。 设备安装工程。
简述教育社会学的研究范围。
健康的传播效果包括以下几个层次？（） 知晓健康信息。 健康概念认同。 态度转变。 采纳健康行为。
What is a rotating item?（） A rotating item is an individual item that is defined with a common item number. An item is designated as rotating because one wants to be able to create individual asset records by using the information (Classification, Specification,and Item Assembly Structure) contained on the item record.。 A rotating item is a set of items that are defined with a specific code. An item is designated as rotating because one does not want to be able to create individual asset records by using the information (Classification, Specification, and Item Assembly Structure) contained on the item record.。 A rotating item is a set of kits that are defined with a specific description and GL. An item is designated as rotating because one has the single cost to manage prefers to be able to create individual asset records by using the information (Classification, Specification, and Item Assembly Structure) contained on the assembly record.。 A rotating item is an individual item that is defined with a common item number and can be a spare part. An item is designated as rotating because one wants to be able to create multiple asset records by using the information (Classification, Specification, and Item Assembly Structure) contained on the item set records.。
变频调速中变频器的作用是将交流供电电源变成（）的电源。
