圆管紊流粗糙区(阻力平方区)的沿程摩阻系数λ与( )。 A.雷诺数Re有关 B. 发布时间:2017-12-31 16:18 │ 来源:www.tikuol.com 题型:单项选择题 问题: 圆管紊流粗糙区(阻力平方区)的沿程摩阻系数λ与( )。A.雷诺数Re有关 B.相对粗糙度ks/d有关C.Re和ks/d有关 D.Re和管长l有关
题型:单项选择题 _______ the whole society care for children as well as their parents, children can grow healthily and happily. A.As soon asB.Once C.The moment D.So long as 查看答案