Due to gravity, layers of originally form
oa) rock; vertically
ob) rock; at an angle
oc) sediment; vertically
od) sediment; horizontally

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

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above

The chromosomal structure that limits the number of cell divisions of a cell is the the chromosomal structure that limits the number of cell divisions of a cell is the kinetochore telomere histones centromere