某试液用1cm比色皿测得透光率为T，若用2cm比色皿测定时，透光率的变化将是（）
A.增加
B.减小
C.不变
D.提高1倍
E.降低1／2
参考答案：B
----- Did your father go to America?
----- No, his boss suggested that he _____ there.
A．not go
B．didn’t go
C．wasn’t going
D．not to go
A．θ1=30°，θ2=30°
B．θ1=30°，θ2=60°
C．θ1=60°，θ2=30°
D．θ1=60°，θ2=60°
