 A. water  B. wind  C. heat  D. coal

 A. oil  B. petroleum gasoline  C. natural gas  D. water

 A. Renewable energy is better for the environment.  B. Renewable energy is not going to run out anytime soon.  C. Renewable energy is easier to use.  D. both A and B

 A. running  B. jumping  C. eating  D. throwing a ball

 A. light energy  B. solar energy  C. chemical energy  D. geothermal energy

 A. windmill energy  B. biomass energy  C. conduction  D. solar energy

 A. convection  B. conduction  C. radiation  D. hydroelectric

 A. heat  B. work  C. force  D. eat

 A. solar energy  B. potential energy  C. geothermal energy  D. biomass energy

 A. fire  B. water  C. wind  D. chemicals

 A. kinetic energy  B. conduction  C. potential energy  D. chemical energy

 A. radiation  B. conduction  C. convection  D. fossil fuels

 A. light energy  B. heat energy  C. geothermal energy  D. solar energy

 A. wind; airplane  B. sun; solar  C. water; hydroelectric  D. wind; windmill

 A. solar  B. light  C. heat  D. chemical

 A. energy  B. work  C. power  D. radiation

 A. potential energy  B. chemical energy  C. biomass energy  D. kinetic energy

 A. hydroelectric energy  B. mechanical energy  C. light energy  D. heat energy

 A. convection  B. conduction  C. radiation  D. kinetic

 A. wood  B. coal  C. oil  D. natural gas