How many chucks could a drill bit chuck if a drill bit could chuck a drill?

I understand where you're going, but you're trying to figure out how to make a pencil while sitting at a desk with a hundred pencils on it. Use a readily available online amortization calculator. Start to finish, you can have the answer in 30 seconds.

I have had both a regular and cardiac MRI. The regular one was no big deal, just kind of hang out and not focus on the confined space. The cardiac one was exhausting. Pretty much a 2 hour crunch/pilates/yoga/cardio session in a hamster tube.

My sense is that they took some backing images, but all of the important imaging was some variation of hold your breath and tense your muscles for 20 seconds, or exhale and tense your muscles for 20 seconds. Basically, intentionally ensure that you are removing any consciously controlled movement so that they can focus just on the heart and try to snap images throughout the beat.

Like taking screen shots of a moving video. 98% will be crap, but you will get some clear images. Now make 50 attempts over 2 hours, and each attempt requires you to hold a 20 second crunch while remaining perfectly still, in a tube. I literally had to rest in my car for 15 minutes before I drove home. Physically beat up.