Through an electron transport chain.
Answer:
Calcitonin stimulates the kidneys to absorb calcium when calcium levels are too low, while parathyroid hormone stimulates the kidneys to excrete calcium when calcium levels are too high.
Explanation:
Structure of the inner ear responsible for hearing: the cochlea
Structure of the inner ear responsible for balance: semicircular canals and the vestibule
I don't know what the lotka thing is, but I'd guess c and d because their coefficients are closer