[Q]: United States has varied geographical characteristics. Take for example, the Mississippi Delta. The delta has vast wetland that gets inundated every year. On the contrary, farther west, the Mojave Desert in Nevada sees very little precipitation or floodwater. Both places are beautiful in their own right, and attract many tourists every year. In which place less metal ions would precipitate, Mississippi Delta or Mojave Desert?
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[A]: Mojave Desert

[Q]: Two neighboring towns had different demographics. Hill town had younger inhabitants, most of them in their 30's and 40's. Lake town was inhabited by elderly people, most of them above 65 years of age. Which town had more people with loss of mental function?
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[A]: Lake

[Q]: Pam and Alice studied Earth's climate and vegetation. Pam studied more about high latitudes (70 to 50N), while Alice studied about lower latitudes (30N to 20S). Which person studied more about alpine tundra?
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[A]: Pam

[Q]: Ken is an avid mountain climber. This year he reached the summits of two mountains, mountain A and mountain B. Mountain A is only 5000 ft tall while mountain B is 15000 ft tall. He has also learned a fun fact that water boils faster and at lower temperature at low atmospheric pressure. In which location Ken would need lower temperature to boil water, mountain summit A or mountain summit B?
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[A]:
mountain summit B