How do i calculate work hours from only a start and finish date and time?

Hello,

I can calculate total hours when a user enters a start date/time and a finish date/time. The kick is I only want to include hours from 2:00 PM to 12:00 AM (10 hour period). So assuming all the start and end times will be in this range, how can i calculate work hours over multiple days? For example: Start date/time = 2/26/13 2:30 PM and end date/time = 2/28/13 10:30 PM. I want my calculated hours to show 28 hours. Please help!!

I found a solution for this, nevermind.