搜题请搜索小程序“爱下问搜题”
问题 单项选择题

常规X线摄片不能观察到早期的骨质疏松，骨密度下降多少才能有阳性发现

A．20%
B．40%
C．60%
D．70%
E．80%

答案

参考答案：B

解析： 常规X线摄片不能观察到早期的骨质疏松，骨密度下降40%时方有阳性发现。

阅读理解

阅读短文，回答问题。 

       Hi, Jack, we're going to have our school sports meeting on the playground next week. It will last three days

from Thursday to Saturday. We have many competitions in running, such as 100-meter race, 400-meter race 

and the relay race. We also have the long jump, the high jump, and so on. I know you're good at running. Would

you please take part in the boy's 400-meter relay race which starts at 10:30 am on Friday? Please be on time, 

wear your sports shoes and take a bottle of water.           

       Good luck to you!               

                                                                                                                                               Yours,

                                                                                                                                               Jim        

1. What does Jim ask Jack to do and why?  

                                                                          

2. When does the boy's 400-meter relay race begin? 

                                                                          

3. How long does the sports meeting last?

                                                                         

查看答案
名词解释

工资幅度
查看答案