食品夹应放在专用的桶内,并应()。 ["A、专人专管","B、专夹专用","C、专夹专放","D、专用专夹"]
浮选机体积不变,矿浆浓度增大,矿浆在浮选机中停留时间()。 ["A、缩短","B、延长","C、不变"]
弧光辐射中的()对人体的危害最大。 ["A、紫外线","B、红外线","C、可见光线","D、放射线"]
采取原状土样的工程地质勘察钻孔,按岩土勘察规范要求钻孔口径不低于() ["A.110mm,","B.91mm","C.75mm"]
成本毛利率的公式应为() ["A、成本毛利率=产品配料成本/毛利×100%","B、成本毛利率=毛利/产品配料成本×100%","C、成本毛利率=毛利/(产品配料成本+费用)×100%","D、成本毛利率=产品配料成本/毛利×100%"]
月少