.Those are model teachers, most of______ 发布时间:2017-06-20 23:24 │ 来源:www.tikuol.com 题型:选择题 问题: .Those are model teachers, most of_________ are young women. A.thatB.whoC.whomD.whose
题型:选择题 “总数为N=500,样本容量是n=50,求出间隔500÷50=10,于是每隔10个抽取一个样本,连续抽样50次。”这是采用( )A.简单随机取样法B.分层随机取样法C.等距随机取样法D.多段随机取样法 查看答案
题型:选择题 下列关于复叠式制冷循环说法错误的是( )。A.复叠式制冷循环通常由两个或两个以上不同制冷剂工作的单级或多级制冷系统组合而成B.复叠式制冷循环通常在低温系统使用沸点较高的制冷剂,而在高温系统使用沸点较低的制冷剂C.高温部分系统中制冷剂的蒸发是用来冷凝低温部分系统中的制冷剂D.低温部分系统中的制冷剂在蒸发时向被冷却对象吸热 查看答案
题型:选择题 Kim bought a total of $2.65 worth of postage stamps in four denominations. If she bought an equal number of 5-cent and 25-cent stamps and twice as many 10-cent stamps as 5-cent stamps, what is the least number of 1-cent stamps she could have bought ?()A.5B.10C.15D.20E.25 查看答案