Answer:
the second option is correct.
An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in CELL TO CELL RECOGNITION.
Carbohydrates have diverse functions, one of their functions is that they serve as a recognition signal at the surface of cells.
Carbohydrates located on the surface of cells enable cells to recognize and communicate with one another.
100%-9%=91%
$819/91%=$900
100%+5%=105%
$900x105%=$945
Answer: He should sell it at $945 to make a profit of 5%.