The system helps (computer) __________ the school’s salary management.
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He gave a lot of money for AIDS (prevent) __________ and relief of other diseases.
He is one of the (rich) ________ and most innovative entrepreneurs in the world.
所有的带传动都是依靠带与带轮的摩擦来传递运动的。（ ）
A. 对
B. 错
同步带传动是一种啮合传动，因此带与带轮之间不会产生打滑现象。
A. 对
B. 错
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