I am trying to calculate the difference between a start time and completion
time and i want to be able to consider business days and business hours.

ie:

start time: 1/16/08 10:24 AM
complete time: 1/18/08 12:40 PM

my time between is complete-start = 2.09
my netbusiness days is 3
but i want to also calculate how many hours but also consider the business
day clock starts at 9am and ends at 5pm.

How do i write a formula to accomplish this?