降低装卸搬运成本可以通过()方法。
A.减少作业次数
B.缩短作业距离
C.提高货物活性
D.增加作业容易度
E.选择恰当的作业方式和方法
参考答案:A, B, C, D, E
洗衣机的脱水筒在转动时有一衣物附在筒壁上,如图所示,则此时( )
A.衣物受到重力、弹力、向心力和摩擦力的作用
B.衣物受到重力、弹力和摩擦力的作用
C.衣物只受弹力的作用,且由其提供向心力
D.衣物受到重力、向心力和摩擦力的作用
It is not rare in ____ that people in ____fifties are going to university for further education.
A.90s, the
B.the 90s, /
C.90s, their
D.the 90s, their