A change in their food, from trees to grass in the Great Plains.
The answer is D: solar energy is a renewable source
The conditions listed above are common side effects of DEPRESSANTS. Depressants are drugs which slowed down the central nervous system an the brain. They are usually used to treat anxiety and sleep disorders. Other side effects of depressants include: slurred speech, impaired memory and judgement, lowered inhibition, etc.
