Hello, I am considering buying a DSLR camera to shoot 4K video. I would like to be able to edit this 4K video footage on my iMac (I use Final Cut Pro). My three questions are: 1. About how much memory is needed for an iMac to smoothly process 4K video footage? 2. How do I check how much memory is already in my iMac? 3. What is the easiest way to efficiently add more memory to an iMac? Note: These days External hard drives are continuously getting less and less expensive. Therefore I am not concerned about hard drive space. I am only concerned about memory processing. Thank you.