Amy is           a library, but she can't           it.      [ ]

A. looking at; find                

B. looking for; find

C. look at; finding                

D. look for; finding

用重量法测定铁试样0.1600g中的铁，获得0.1300gFe₂O₃.试样中Fe%的计算式为：（）

A.0.1300（×）2Fe/Fe₂O₃（×）100/0.1600

B.0.1300（×）Fe₂O₃/2Fe（×）100/0.1600

C.0.1300（×）Fe/Fe₂O₃（×）100/0.1600

D.0.1300（×）Fe/2000（×）100/0.1600

E.0.1300（×）Fe/1000（×）100/0.1600