Answer:
because there might be changes in the future which could make the estimates unreliable for example war or decline in economy
Explanation:
Answer:
I believe picking new president
Color hardness Streack clevage or fracture
Hydrogen is used by plants which combine it with carbon during the photosynthesis process and release oxygen into the atmosphere which is used by all living beings.
Straight to the surface of the earth and cause some serious problems
