What makes elements and compounds different from mixtures? Elements and compounds- a). have a constant composition
b). are made of gases
c). will not change when heated
d). conduct electric current

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

In the ocean why are the greatest amount of primary producers found in the epipelagic zone and how does that affect biodiversity

What is gene flow? apexa: selection for average traits b: when a population splits in twoc: a mutation becoming more commond: genes moving between two populations