Which of these results when hormone secretion is regulated by a negative feedback mechanism?

all hormones are regulated by other hormones.
hormones determine the metabolic rate of all cells.
hormone concentrations rise and fall depending on the time of day.
the concentration of a hormone remains within a narrow normal range.

For the strategies below, decide whether they are best described as demand-side solutions or supply-side solutions to meeting human needs for fresh water. remember that a demand-side solution reduces demand for fresh water, whereas a supply-side solution increases the supply of fresh water. (a) damming a river to create a reservoir (b) desalinating seawater (c) a nation invading a neighboring country to access their rivers (d) raising water prices for consumers and businesses (e) providing tax breaks for companies that use less water (f) replacing inefficient irrigation with more-efficient drip irrigation to grow crops (g) requiring low-flow showerheads in all new homes