He has learned________,no matter what happens and how bad________seems today,life goes on

and it will be better tomorrow.[ ]

A. that;  it  

B. it;  that

C. it;  it  

D. that;  that

机械设备安装中进行水平度调整（找平），通常在设备精加工面上选择测点用（）进行测量。

A.水平仪

B.经纬仪

C.全站仪

D.百分表