D. 1,200
This is because if it takes 1 and a half hours **1.5** to travel through city a and city b , and the plane goes 800km per hour and 400km is half of that it then the answer has to be d.
They replace the lost ions by active uptake through active transport
of ions from the surrounding waters. This is exhibited in freshwater fishes that
actively take in these ions through the gills. Most of the ions involved in osmoregulation in freshwater are those of Na+ and Cl-.
I think the answer is B sorry if I’m wrong
<span>The answer to this question would be: hypertonic, hypotonic
After eating, the intestine is filled with food that will be digested. Food that digested will turn into a much smaller unit of carbohydrate, amino acid and fatty acid that will cause the intestine to have hypertonic solution compared to the blood. This will induce diffusion of some molecule to the intestinal cell, and then to the blood.</span>
