On a hot day, the upstairs rooms in a house are usually hotter than the downstairs rooms. why? a. cool air is less dense than warm air. b. warm air rises and cool air sinks. c. the upstairs rooms are closer to the sun. d. heat rises.

i'm pretty sure it's spores

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.

sorry, but you do not have posted the diagram.

c should be the answer