Answer:
1 and 3
Explanation:
1.Melting is a reversible change because it can be frozen back to its original state.
3. Decomposition involves breaking down of large substances into new smaller ones with release of energy which is similar to a chemical reaction
2. Decomposition isn’t usually reversible because new substances have been formed due to microbes and environmental conditions. A decayed substance can’t be changed back to its original form
