Which organisms convert nitrogen into a form that is usable by
humans

Living cells cannot use heat to provide the activation energy for biochemical reactions because which choice(s) complete the sentence correctly? a) answer choice ii. eliminate b) answer choices ii and iv. c) answer choice iii and iv. d) all answers can complete the sentence.

Sediment layers stop lateral spreading when: they encounter a barrier they encounter an opposing current they run out of additional sedimentary material

Aquaternary consumer species would be expected to have a smaller population than a secondary consumer species. select the best answer from the choices provided t f