It's 1. Melting a substance. The rest are chemical changes
Answer:
2Mg^+ +O2 right arrow 2MgO
Explanation:
Answer:
Energy in an ecosystem comes from the Sun.
Explanation:
It is a major source of energy for organisms, plants and the whole ecosystem basically.
B. Most rocks are composed of single mineral
Answer: The answer would be D.
Explanation: When a screw is tightened into an object, it is wedge in between.
