How do valence electrons determine the reaction between sodium and chlorine

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

4the indian leaf butterfly has traits that allow it to resemble a leaf. the bright colors of the monarch butterfly indicate that the butterfly tastes bad and can be poisonous. how does the appearance of these butterflies them to survive? f the indian leaf butterfly is able to avoid predators while the monarch butterfly warns predators away. g. the indian leaf butterfly frightens predators away while the monarch butterfly poisons predators before they can eat it. h both butterflies rely on camouflage to avoid predation. j both butterflies cooperate with one another to avoid predation.

What are the two main phases of a cell cycle