1) true
2) Yes resting heart rate does measure the beats per minute but specifically when your body is not in motion. (Typically sitting on a couch or chair)
Do you have multiple choice to chose from? If so, what are they?
D. It isn't good to rush into new exercises, and he needs to be more in shape than just stretching
The food wouldn't have the full nutritional value anymore and (depending on what it is) you could be at risk for food poisoning or simply an upset stomach.