Answer:
substance
Explanation:
A pure substance is a form of matter that has a constant composition (meaning it's the same everywhere) and properties that are constant throughout the sample (meaning there is only one set of properties such as melting point, color, boiling point, etc
I think the correct answer is b. Temperature is proportional to the average kinetic energy so when temperarure rises so will the average kinetic energy. I hope this helps. Let me know if anything is unclear.
Hopefully this will help you my friend.
