How to subtract 2 dates and times from each other excl weekends, holidays and only considering working hours during the day?

[Pharming]

I am struggling to find the right formula for the following problem.

I need to subtract 2 dates & times from each other but exclude holidays, weekends and keep the hours only between 07:00-16:00. May someone please assist? I don't want to just copy and paste a formula, I want to understand it.

 

[Micron]

I pasted your question into a browser search bar and got a couple of hundred hits with examples and videos. I'm not a formula guy in Excel so I didn't take the time to do more than a cursory review. Looks to me like the answers would at least get you started, so that might be a good place for you to begin.