When comparing village A from ten thousand years ago to village B from today, we reached the conclusion that today's villagers release much more carbon into the atmosphere by their activities. Which village burned fewer fossil fuels?
Ans: village A

Beijing recently opened several new coal-fired power plants over the last few months. In Montreal, there have been large reductions in sulfur oxides produced by manufacturing plants after a recent referendum. Which area is less likely to have acid rain?
Ans: Montreal

Gary and Joe are two farmers. Joe's farm has a depleted soil, while Gary started agroforestry a few years back, and grows cover crops. Which farmer helped to stabilize the soil more?
Ans: Gary

Robin and Samantha are both bodybuilders preparing for a competition. Both of them are trying to change their skin complexion to help their appearances at the competition. Robin begins exposing her skin to high amounts of UV light several days a week. Samantha decides not to use any UV light and instead just uses lotion to help her skin. Who will produce higher amounts of vitamin D?
Ans: Robin