In one of her epeditions, a marine biologist finds a new organism that has an unsegmented, radially-symmetrical body with spiny skin. under witch phylum should she classify this organism annelids arthropods echinoderms mollusks

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.

i think it is dna, i'm not totally sure but i think it might be.