Answer:
Practice exercise 2:
Water is a liquid, if I cool it, it will become solid and if I remove it in the freezer it will turn into a water. This is a reversible change, because if I cool the water it will turn back into a solid.
Practice exercise 3:
1. The material will change
2. The material will remain the same
3. The material will change
4. The material will remain the same
5. The material will change
