学礼仪三个基本理念是:() ["A、尊重为本","B、善于表达","C、形成规范","D、好的习惯"]
计算题:当制动缸压力为350KPa时,若制动缸内径为152mm,求一个制动缸的制动原力?
送礼应注意什么:() ["A、礼品的定位","B、礼品的贵重程度","C、礼品的选择","D、送礼品的时机"]
座次排列非基本规则:() ["面门为上","以左为上","居中为上","离远为上"]
会客的座次排列分:() ["自由式排列","相对式排列","并列式排列","一排式排列"]
计算题:有一弹簧,工作圈数为10圈,弹簧直径D=50mm.簧丝直径d为8mm.G=80GPa.受拉力P=100N。计算弹簧的伸长量(L=PDn/Gd)