题目

阅读短文，根据短文内容回答问题。Email helps workers to communicate at any time, from any place. Email is an important tool, but it can also lead to a waste of time. How can workers make sure that email is a tool and not a time-waster? Here are some simple tips to follow. They can help you use email more efficiently (高效地) at work.First of all, turn off the sound in your computer that tells you that you have a new email message. That “You’ve got mail!” sound is like a telephone or a doorbell. It interrupts your work. When you hear it, you will want to check your messa6．下列物质中不属于合金的是（　　）A．铁锈B．钢C．青铜D．黄铜