题目

Perhaps you have heard a lot about the Internet,but what is it,do you know?The Internet is a network.It uses the telephone to join millions of computers together around the world. Maybe that doesn’t sound very interesting.But when you’ve joined to the Internet,there are lots and lots of things you can do.You can do with all kinds of information on the World Wide Web (WWW).You can use QQ to chat with your friends,and they will make responses in a few seconds.You can send E-mails to your friends,and they can get them in a few seconds.You can also go shopping by the Internet without go以下是生活中常见的几种物质，其中属于氧化物的是（　　） A、硫酸B、碳酸钙C、蔗糖（C12H22O11）D、二氧化碳