题目

Did you ever count the number of digits (数字) in your mobile phone number? Your number has 11 digits. You may sometimes find it hard to remember your number. That’s because China has the longest mobile phone numbers in the world. Why is that?We can group the 11 digits into three parts. Each part has a different meaning. The first three numbers tell you which mobile phone service company you are using. For example, 135 is for the China Mobile Communications Corporation (中国移动) and 188 is for China Unicom (中国联通). The fourth to the seventh digits tell you where the number is r托里拆利实验的主要器材是一根________和________，1atm的值等于________Pa．