The creation of a communications hotline between the United States and the USSR was a result of the end of the Cuban Missile Crisis. The answer to your question is B. I hope this is the answer that you are looking for and it comes to your help.
Pollution from a near by city is your answer ;D
Answer:
The discovery of Chromosomes
Explanation:
by growing tress and by putting down hydro mulch as needed
Water on the earths surface is HEATED and RISES into the air as WATER VAPOR
