实验室以介质进行离心泵特性曲线的测定,在转速为2900rpm时测得一组数据为:流量3.5×10 -3 m 3 /s,泵出口处压力表读数为100kPa,入口处真空表读数为6.8kPa。电动机的输入功率为0.85kW,泵由电动机直接传动,电动机效率为52%。已知泵吸入管路和排出管路内径相等,压力表和真空表的二测压的垂直距离为0.1m,试验水温为20℃。试求该泵在上述流量下的压头、轴功率和效率。
【单选题】( ) is a discretionary act, and is not a legally sanctioned function of the jury. It is considered to be inconsistent with the jury's duty to return a verdict based solely on the law and the fact...