Speciation occurs when 1. a new species mate with the old species.
2. a new species formed from existing populations.
3.All answers are correct.
4. a new organism was formed from nowhere.

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

acceleration= v2-v1/t so 8m/s-3m/s / 3s =to 8/3 or

2.67 m/s^2

hope i

-lavira: )