建材买卖中，售沙人常将沙堆成拟柱体。
While in doing building materials business , the sellers often pile sand up with quasi-prism .
如何测算拟柱体的体积是公平交易的关键问题之一，本文深入研究了这一问题。
How to work out its volume becomes the key to a fair deal , this paper makes a deep study on that .
拟柱体