Answer:
1. fission
2. both
3. fusion
4. fusion
5. fission
Step-by-step explanation:
Fission refers to the splitting of a single nucleus into two or more small nuclei while fusion refers to the combination of two or more small nuclei into one heavy nucleus.
When a single heavy nucleus splits, energy is released and the end products are 2 or more lighter nuclei. On the other hand, when several light nuclei fuse into one nucleus, energy is absorbed and the end product is one heavy nucleus. Both fission and fusion result in a nuclear change.