简述磨机磨音随料球比的变化？

综合填空（根据短文所给首字母完成下列短文）。

Dear Mum,

    I don't think you understand my life. You think I should be s________(1) all the time. I know you want me

to f________(2) a good job when I grow up, but I would like to have a w________(3) time, too. You never

think about fun things for me to do like music, sports. Two days ago, w________(4) I was w________(5) a

football game on TV, you asked me to stop and do my homework. After f________(6) my homework, still I

wasn't a________(7) to read my football magazines. You said I had to go to bed e________(8). That was bad.

Especially yesterday was the worst day. I bought some CDs, and put them in my bag so that you wouldn't see

them. I told you I had to do my homework first. I know it was w________(9) to lie (说谎) to you. But after

you knew the truth you told Dad. Mum, I didn't quite like what you did to me! I really love you, Mum, but I

w________(10) you could give me some freedom.

经验证明，要使一个国家或地区的生态环境比较优越，其森林覆盖率要达到 ( )

A．10%

B．20%

C．30%

D．40%

GPS定位的实质就是根据高速运动的卫星瞬间位置作为已知的起算数据，采取( )的方法，确定待定点的空间位置。

A．空间距离后方交会

B．空间距离前方交会

C．空间距离侧方交会

D．空间角度交会

下列描述正确的是（）

A.仪器、仪表必须定期检验，保证其精度。

B.承建单位在为建设单位安装室内分布系统的地点可以再为其他运营商安装同类设施。

C.承建单位应在工程开工前1个工作日以上，提交开工报告。

D.在驻波比测试、天线口功率测试过程中严格按测试要求和规范进行，认真填写相关记录，并在五个工作日内提交给监理单位核对。