Calculating Net Working Hours.

What do you have in K$1 and K$2..?
The formulla is working but not giving exact result.. i put the start time as 3/13/2008 10:00 in A2 and =now() in C2 (My current time is 3/14/2008 3:33 AM, I am in India) it is showing "Age of ticket = 4:46"
however it should show "Age of ticket =7:00" as working hours ends at 17:00 PM.
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I AM SORRY... IT WAS MY MISTAKE...
IT WORKED.. I DIDNT NOTICED WHAT YOU WRITTEN FOR K2 AND K3...
THANK YOU THANK YOU THANK YOU THANK YOU THANK YOU THANK YOU THANK YOU VERY MUCH......

Can i have your email id so that i can contact you if i need any help in future....?