<span>I believe the answer is: D. proteins
The main functions of these proteins is to allow specific substance to pass through the membrane of the cells which needed for the energy formation for cells'functions.It created through the combination of more than 20 amino acids with different functions.</span><span />
Animals that use echolocation. Bats, whales, dolphins, a few birds like the nocturnal oilbird and some swiftlets, some shrews and the similar tenrec from Madagascar are all known to echolocate.
Answer:
b. quantitative observation
if its wrong sorry.
hope this helps you ☺️☺️
The answer: True
if not it wouldn’t continue to more or it wouldn’t be steady