Question! Earth's atmosphere is warmer than it would be without a
greenhouse effect. Which form of energy is absorbed
by the atmosphere and mainly causes this increased
temperature?
a) Radio waves.
b) Infrared.
c) Visible light
d) Ultraviolet

In the greenhouse effect, it absorbs infared energy to cause an increase in temperature, so the answer would be B.

answer; in the united states the plains include the great plains of the west and the tail grass prairie to the south of the great lakes extending east to the appalachian plateau