Because they can make energy, is free to anybody, and can be found everywhere that you go.
Answer: D
Explanation:One of the reasons for this is that there is little or no magma available at the plate boundary. The most common magmas at constructive plate margins are the iron/magnesium-rich magmas that produce basalts.
Answer:
b. Aldosterone promotes sodium reabsorption in the kidneys.
Explanation:
Once it is produced by the adrenal gland it stimulates the mineralocorticoid receptors on the distal tubule and collecting duct of the kidney's nephrons. This causes sodium reabsorption in the kidneys indirectly affecting water retention.
Polymerization would be the answer you're looking for.