I have entered food water shelter air it is still wrong. I can't close it either.

I do not know what is going on with the first one, but the second one seems to be

top to bottom:

dopn-pond-duck

ysk-sky-bird

delfi-field-cow

dans_endu-sand_dune-ant/termite

acone-ocean-shark

storfe_loofre-?-crab

etre-tree-squirrel

Hope this helps, I will work on the first part immediately, if this doesn't help comment down below please!!!

the index of refraction of the second medium is higher. i just took the test trust me !

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.