Which statement describes the chemical property of copper that results in the formation of tarnish?
O A. It does not burn.
O B. It has a very high boiling point.
C. It has a low density.
O D. It reacts easily with other substances.

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere