“嫦娥二号”是我国月球探测第二期工程的先导星．若测得“嫦娥二号”在月球(可视为密度均匀的球体)表面附近圆形轨道运行的周期为T，已知引力常量为G，半径为R的球体体积公式V＝πR³，则可估算月球的(　　)．

A．密度

B．质量

C．半径

D．自转周期

The book didn't ____ children probably because the author employed too many scientific terms in it.      [ ]

A. apply to    

B. appeal to  

C. intend to    

D. lead to