液压泵单位时间内排出油液的体积称为泵的流量。泵在没有泄漏的情况下,根据泵的几何尺寸计算而得到的流量称为( ),它等于排量和转速的乘积。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
免费的网站请分享给朋友吧