how many units of energy would there need to be in the first trophic level to end up with 1000 units of energy in the second? in the third? in the fourth?

Prokaryotic and eukaryotic cells are different in many ways other than the presence or absence of a nucleus. if both archaebacteria and eubacteria are prokaryotic cells, then why are archaebacteria more closely related to eukaryotic cells than they are to eubacteria?