Ground- Source Heat Pumps Use the Difference in Temperature Between

Multiple Choice

Ground- source heat pumps use the difference in temperature between the air and soil to warm and cool buildings. The upper 10 ft of the Earth is always at a constant temperature of_______, which is ideal for warming buildings in the winter and cooling them in summer.

A) 50- 60°F
B) 225- 60°F
C) 70- 80°F
D) 100- 20°F
E) over 360°F