齿数模数为（）之比值。
A.节圆直径与齿数；
B.节圆半径与齿数；
C.节圆周长与齿数；
D.齿轮外径与齿数。
参考答案：A
阅读排序。阅读下列各句，根据其内容重新排列所有句子的顺序，使其构成意义完整正确、逻辑顺序合理的语篇。
Someone says, “Time is money.”
A．That’s why we can’t waste time.
B．But I think time is even more important than money.
C．However, when time is gone, it will never return.
D．In a word, we have no time to waste, so we should cherish time.E．Because when money is spent, we can get it back.
下列程序段执行后的输出结果为 int x=3； int y=10； System.out. println(y %x) ；
A．0
B．1
C．2
D．3
