两变量为正相关,则() A.∑(X-)(Y-)为正 B.∑(X-)(Y-)为负 C. 发布时间:2017-09-07 04:19 │ 来源:www.tikuol.com 题型:单项选择题 问题: 两变量为正相关,则()A.∑(X-)(Y-)为正B.∑(X-)(Y-)为负C.∑(Y-)大于∑(X一)D.∑(Y-)小于∑(X-)E.X变量大于Y变量
题型:单项选择题 The bad weather meant ______ the rocket launch (发射) for 48 hours . A.delayingB.having delayedC.to delayD.to have delayed 查看答案