若公比为2且各项均为正数的等比数列{an}中,a4•a12=64,则a7的值等于 发布时间:2017-05-01 03:05 │ 来源:www.tikuol.com 题型:选择题 问题: 若公比为2且各项均为正数的等比数列{an}中,a4•a12=64,则a7的值等于( )A.2B.4C.8D.16
题型:选择题 Walmart, which is one of the largest American supermarket chains, _______ some of its store open 24 hours on Mondays through Saturdays.A.keepB.keepsC.have keptD.had kept 查看答案