The vena cava pumps blood from the heart to the rest of the body a. true b. false

Why are small quantities of chlorofluorocarbons so harmful to the ozone layer? a. the chlorofluorocarbons act like ultraviolet radiation causing large amount of ozone to be produced. b. the chlorine from the chlorofluorocarbons reacts with free molecules of oxygen causing a stop in ozone production c. free oxygen atoms can replace the chlorine in chlorine monoxide, releasing a free atom of chlorine which can then recombine with an oxygen atom in ozone, destroying more ozone. d. chlorofluorocarbons absorb ultraviolet radiation, preventing the formation of ozone select the best answer from the choices provided

Apaleontologist finds a plant fossil that shows that the plant had seeds. what can the paleontologist conclude?

Other than earth, is also known to have magnetic pole reversal? a: venus b: mars c: earths moon d: the sun