I would like to type in a number and if the number meets a certain criteria,
return that number with a unit identifier.

I.E. a number "A1<= 9.9" returns "value for A1GHz" and if "A1>=100, A1<=999"
returns "value for A1MHz"

I would to type a single place, decimal digit under 10 and get that value
with the unit identifier "GHz". By the same token, if the number is greater
100, but less than 999, show the value with the identifier "MHz".

Thank You