无砟轨道Rheda2000300型扣件安装包括（）A、预埋绝缘套管 B、铺设弹性底垫 发布时间：2019-12-21 23:26 │ 来源：www.tikuol.com 题型：多项选择题 问题： 无砟轨道Rheda2000300型扣件安装包括（）A、预埋绝缘套管B、铺设弹性底垫板、底板、轨垫C、安装轨距挡板D、安装弹跳、螺栓和绝缘垫片
题型：多项选择题 阅读下列短文，根据短文中的信息完成文后表格。(每空一词) The Internet is becoming more and more important in our life. How much do you know about it? Whatis the Internet? The Internet is a large, worldwide collection of computer networks. A network is a small group of computers put together. The Internet is many different networks from all over the world. These networks are called the Internet. Once you have learned to use the Internet, you can have a lot of interest in the World Wide Web. What is the World Wide Web? The World Wide Web is the most popular development (发展) of the Internet. The Web is like a big electronic (电子的) book with millions of pages. These pages are called homepages. You can find information about almost anything in the world on these pages. For example, you can use the Internet instead of a library to find information for your homework. You can also find information about your favourite sports or film stars, talk to your friends or even do some shopping on the Internet. Most pages have words, pictures and even sound or music. What is e-mail? An e-mail is a way to send messages to others. It's much quicker and cheaper than sending a letter. If you want to send e-mails, you must have an e-mail address. This address must have letters and dots (点) and an '@' (meaning 'at'). This is what an address looks like: Emily @ star. net. Write a message, type in(输入) the person's e-mail address, and then send the message on the Internet. People don't need to use stamps, envelopes(信封) or go to the post office since the invention of the Internet. Quick. easy and interesting — that's the Internet!What is the Internet?The Internet is a large, worldwide __1__ of computer networks. It is many different networks from the __2__ world.What is the World Wide Web?The World Wide Web is the most __3__ development of the Internet.What is e-mail?An e-mail is a way to send __4__ to others.What's the character of the computer?__5__, easy and interesting — that's the Internet! 查看答案
题型：多项选择题 已知数列{an}，{bn}是各项均为正数的等比数列，设cn=bnan，n∈N*（Ⅰ）证明：数列{cn}是等比数列，数列{lnan}是等差数列．（Ⅱ）设数列{lnan}，{lnbn}的前n项和分别是Sn，Tn．若a1=2，SnTn=n2n+1，求数列{cn}的通项公式．（Ⅲ）在（Ⅱ）条件下，设dn=6cnbn+1-4an+1-4an+2 ，求数列{dn}的前n项和． 查看答案
题型：多项选择题 大肠菌群是由几个属的细菌组成的，那么这些细菌是（）。A.大肠埃希氏菌属的细菌、柠檬酸杆菌属的细菌、阴沟杆菌属的细菌B.产碱杆菌、克雷伯氏菌属的细菌、大肠埃希氏菌属的细菌、柠檬酸杆菌属的细菌C.产碱杆菌、克雷伯氏菌属的细菌、大肠埃希氏菌属的细菌D.克雷伯氏菌属的细菌、大肠埃希氏菌属的细菌、柠檬酸杆菌属的细菌 查看答案