Which of the following events occurs first? a)the brain sends a signal to the muscles b)the blood vessels just under your skin become narrow c)the hypothalamus detects a drop in body temperature d)you shiver

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.

c. establishing proper sleep hygiene