Solar represents a minuscule portion of U.S. energy production because of           

Placer mining involves the use of _____.

A potential energy source from oceans is ______

All of the following are anthropogenic factors contributing to climate change EXCEPT ______.

Which of the following methods is considered a type of passive solar energy collection?

Environmentalists and scientists advocate immediate intervention regarding global climate change because_________ .

The most recent analyses of polar ice cores have given us the ability to profile global climate change back as far as   ____years.

Wind energy has been harnessed for hundreds of years to______

Surface impoundments are _______.

Acid mine drainage often contains heavy metals