我国第一个南极考察基地“长城站”在()落成。A.1980.2 B.1981.2 C. 发布时间:2017-07-04 15:37 │ 来源:www.tikuol.com 题型:单项选择题 问题: 我国第一个南极考察基地“长城站”在()落成。A.1980.2B.1981.2C.1985.2D.1986.2
题型:单项选择题 各项均为正数的数列{an},a1=12,a2=45,且对满足m+n=p+q的任意正整数m,n,p,q都有am+an(1+am)(1+an)=ap+aq(1+ap)(1+aq)(I)求通项an;(II)记cn=an+1-an(n∈N*),设数列{cn}的前n项和为Tn,求证:对任意正整数n都有Tn<23. 查看答案
题型:单项选择题 ①量筒②试管③烧杯④酒精灯⑤广口瓶⑥滴管,用上述仪器的序号填空:用来盛放少量药品进行化学反应的仪器是______;量取一定量液体体积的仪器是______;给物质进行加热的仪器是______;贮存固体药品的仪器是______. 查看答案
题型:单项选择题 -Has your father returned from Africa yet? -Yes,but he __________here for only three days before his company sent him to Australia. [ ]A. was B. has been C. will be D. would be 查看答案