B; As far as the relation between humans and the environment, it is obvious how much they relied on it. Not only as a food source, but for economic growth and sustainability as well. The other answers make valid points but in the context of this question, the only one that even mentions the relation is B.
Fire is important because it cooked food, provided light and provided heat
Answer:
they work together
Explanation:
think of nemo. they live in the anemone and eat it (clean the stuff off) and in return they provide a place for the fish to live
Hope this helped even the slightest :)
Answer:
A particle or packet of light.
Explanation:
A photon essentially doesn't have a charge and thus can't be called an electron. So, option 1 is incorrect.
Photons are in fact packets of electromagnetic energy that light is made up of. So, option 2 is correct.
A photon is not a gaseous mass that indicates the preliminary stage in a star's growth and thus can't be a protostar. So, option 3 is incorrect.
Photons having different energies are constituents of the electromagnetic spectrum and thus a single photon can't be a spectrum. So, option 4 is incorrect.