Which is not a question you should ask to you draw a conclusion?
a. are there any improvements you can make to the experiment?
b. how do the data compare with what you already know?
c. how can you change the data to fit your hypothesis?
d. is there a trend in the data?

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.

because they are eaten by the frog and the frog getseaten by the snake and the snake by the eagle