Explain why you cannot cool your kitchen by leaving refrigerator door open

No, no you can not

Explanation: It will probably spoil the food, or make the food inside the fridge hot when it needs to be cold. Plus it will just let all its coolness out so it won’t work.

(b) which contains higher levels of vitamin b, oranges or spinach?

explanation:

you can eliminate a, c, and d because they are questions based on opinions.

yes the answer is total mass in unchanged   : )