Answer:
The Nile River
Explanation:
The Nile River is more than 4,000 miles long and is considered to be the longest river in the world. It runs through many countries in northeastern Africa.
Nuclear fusion generates the energy that is released by stars.
In the great majority of stars, it's the fusion of hydrogen nuclei
to form helium nuclei plus energy. In very old stars, the nuclei
of heavier elements are fused, forming even heavier ones.
Answer:
If on a flat surface, it will widen and flow freely until friction stops it.
Explanation:
I think that a) is chemical, and b) would be chemical