Filter amount between two columns "A" and "B"...

Hi!

I need to know how to filter amount between two columns ("A" and "B") in one database.
On my form I have the textbox1 and the label1.

For example:

I need to filter the amount 29,500 between column "A" and "B". In wich interval of those two columns could be find it? It's between 25,001 and 30,000. Then when find that row its should show the number "5" on label1. 

How could be possible???

Database "Test"

     A     |      B      |    Percentage
----------------------------------------
25,000  |      0      |          0
25,001  |  30,000  |          5
30,001  |  35,000  |          6