Ferns<span>, </span>horsetails<span>, </span>mosses<span>, and </span><span>liverworts, flowers, mint</span>
I believe the answer is the weight of each tomato.
This is because the weight of each tomato depends on the amount of fertilizer (the independent variable/the thing being changed) added to each plant.
A situation where friction would be desirable is rubbing your hands together to make them warm in the winter time.
Aldosterone increases the reabsorption of sodium ions bringing more back into the blood.
<span>This is the main mineralocorticoid hormone of the adrenal gland. The function of the aldosterone is in the homeostatic regulation of blood pressure, plasma sodium (reabsorption) and potassium levels (excretion).</span>