Explanation:
When two small nuclei combine together to form a large nuclei then it is known as nuclear fusion.
When nuclei of two hydrogen atoms fuse together then it results in the formation of a helium atom along with the release of lot of energy. This energy is nuclear energy.
This nuclear reaction is as follows.

Thus, we can conclude that nuclear fusion represents nuclear energy.
Answer:
The formula for volume of a rectangle is length multiply by width multiply thus, 0.25 m multiply 6.1 m multiply by 4.9 m = 7.5m^3.
Explanation:
the least number of significant figures is 2 thus the final answer will have the same number of significant figures. 7.5m^3
1. Energy can neither be created or destroyed.
2. Conduction. Putting a pot of water on a hot burner. Convection. Putting your wet shoes over an air vent to dry them quicker. Radiation. Sitting in front of the fire to warm your hands up.
3. renewable sources can be used again and again, but non renewable sources cannot.
4. I would recommend solar energy. I think solar energy should be considered because solar energy can be reused, and also because they can use it to power their houses and they wouldn't need fossil fuels to do so.
5. Turn off the lights and open the windows during the day and if something is left plugged into the wall and it is not being used, unplug it.
hope I could help!