Ben and Andy studied minerals and micro-nutrients. Ben studied more about magnesium, zinc and molybdenum, while his buddy Andy studied about sodium and potassium. Which person studied more about positively charged ions?
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Answer: Andy

Two cities had different energy source. Big city burned fossil fuels cut forests and cleared land, while Blue city used alternative sources of energy. Which city destroyed fewer autotrophic organisms?
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Answer: Blue

Two continents had different histories. Asia was inhabited by many humans which destroyed most natural habitats through their activities. America was protective towards its environment and therefore thrived. Which continent didn't destroy habitats by land use change?
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Answer:
America