题目

对于简单随机抽样，下列说法正确的是  （ ）    A．从总体中逐个不放回地抽取样本为简单随机抽样    B．从总体中抽取样本，满足每个个体被抽到的机会相等的抽样为简单随机抽样    C．设一个总体含有N个个体，从中逐个不放回地抽取n个个体作为样本（n≤N），如果每次抽取时总体内各个个体被抽到的机会都相等，这种抽样方法叫简单随机抽样    D．以上均不对  根据上下文和你的实际情况把下面的对话补充完整。A: Hello! May I speak to Tina, please?B: Speaking. ________【1】_______?A: This is Bill. I called you yesterday, but you were not at home. _________【2】______?B: I went shopping yesterday. I need to buy something for my trip to Tibet.A: Tibet? _____【3】_____？B: Because the scenery there is really beautiful. A: Oh, yes, It’s said that there is the most beautiful sky.B: Yes. By the way, what do you call me for?A: I’ll have a birthday party next Friday. _____【4】_______?B: Oh, I’d love to, but I’m afraid I can’t. My plane will take off next Wednesday.A: What a pity that you can’t come! ______【5】______!B: Thank you very much, Bye !A: Bye!