Question

1. where does nuclear fusion happen? 23. what are three ways we use nuclear fission here on earth?

Explanation:

Nuclear fusion occurs in the sun's core due to high - temperature and pressure conditions allowing hydrogen atoms to combine. Nuclear fission is used in nuclear power plants to generate electricity, in nuclear weapons for explosive force, and in some medical applications like radioisotope production.

Answer:

1. In the core of the sun (and other stars).
2. In nuclear power plants for electricity generation, in nuclear weapons, in medical radioisotope production.