Objective:To understand the knowledge level and attitude of school students about AIDS and their behavious factors,and to provide accordance for school propagand plans.

目的了解中专生滋病知、态、行现状，为学校滋病宣传策略提依据。

The paper expounds in detail the relation between oil density and metering and suggests that it is necessary to propagand metrical knowledge to customers.

详细阐述了存收发过程中密度与计量的关系,并提出了向客户宣传计量知识的必要性。