The question is incomplete but i will try to answer it to the best of my ability.
Answer:
See explanation
Step-by-step explanation:
A nuclear power plant operates by a chain reaction. A nuclear power plant usually uses a uranium fuel. The fissile isotope of uranium is U-235.
This reaction is a chain reaction in the sense that the neutrons produced bombard more uranium atoms leading to a self-sustained chain reaction. Control rods and moderators are used to keep the chain reaction under control.
The equation of the chain reaction is depicted in the image attached to this answer.