试述路由器的主要服务功能。
参考答案：
-Which band do you like best, madam?
-I can't decide now, I really don't know_________.
A. to choose which one
B. choose which one
C. which one to choose
D. which one I should choose it
适于装在棕色酸式滴定管中的是（）。
A.H2SO4
B.NaOH
C.AgNO3
D.K2S2O3
