What effect does an increase in greenhouse gas concentration have on the energy budget of the Earth?

Which of the following best describes the economy of africa?

Acivilization exists for several hundred yeaars, developing its own language. such a civilization probably has been: a. farming corn b. suffering from a lack of contact with the outside world. c. isolated by mountains or some other physical barriers. d. starving from lack of trade.

Which of these fragmental sedimentary rocks would most likely form farthest from the land?