As of now, the nuclear fission is the most feasible energy source for human use. All the nuclear power plants are based on the controlled nuclear fission reaction, where the unstable nucleus is bombarded with high speed neutrons, thus, splitting the nucleus into stable ones and releasing huge amount of energy. The nuclear fusion requires very high temperature, the temperature equal's to that of the sun. Hence, it is not feasible right now. As the technology advances, we will see advancement in other form of energies.
Let's go through each of the answers and think about why they work or don't work.
Chemical forms compounds.
Nuclear changes the element completely. We're going to use the sun as an example. The sun is in a state of plasma. It's really hot and has all these particles hitting into each other. The nucleus' of atoms are hitting into each other forming larger elements. It's real crazy. Nuclear is not correct.
Physical cannot form a compound.
1/15 is the correct answer I think
