7) Nuclear energy is not popular because of which of the following (2pts) fears. nuclear plants put out a lot of carbon dioxide O uranium is very expensive to mine. O inefficiency. radioactivity fears 8) Which country has the largest percentage of its electrical energy coming from nuclear power (2pts) plants United States France Russia China 9) . Which of the following are variable sources of clean energy? (Sections 4.9, (2pts) 4.10) hydroelectric and geothermal. O tidal and hydroelectric. geothermal and solar. solar and tidal 10) What is a possible pitfall of a hydroelectric project? (2pts) Could cause flooding and render land agriculturally unfit. O it is not a continuous source of energy. Does not produce much electricity. O puts out too much carbon dioxide. 11) What has been effective in cutting Brazi's gasolene use and lowering its CO2 emissions (2pts) significantly? (4.12) corn ethanol wind energy sugarcane ethanol nuclear energy. 12) Why is natural gas not used as much as oil (2pts) DO it puts out more CO2 when used than oi. it is not as economical. O it cannot be liquefied to ease transportation while oil is a liquid. O it is scarce. (2pts)