安全电压应根据（）等因素选用。 A.作业场所 B.使用方式 C.操作员条件 D.供电 发布时间：2018-02-28 10:23 │ 来源：www.tikuol.com 题型：多项选择题 问题： 安全电压应根据（）等因素选用。A.作业场所B.使用方式C.操作员条件D.供电方式E.线路状况F.设备状况
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 用如图所示的实验装置研究电磁感应现象。当有电流从电流表的正极流入时，指针向右偏转。则当把磁铁N极向下插入线圈时，电流表指针向_____偏转；当把磁铁N极从线圈中拔出时，电流表指针向_____偏转 查看答案
