Problem: Peter visited two mountain ranges last summer. The Ozarks in Missouri, and the more massive and younger Colorado Rockies. He loved both ranges, but liked the caves systems and blue holes in the Ozarks a bit more. Which mountains have a smaller percent of limestone?

A: Rockies

Problem: Park city used fossil fuels to produce their electricity. They were less conscious about the environment than their neighbors from Lake city. People from Lake city used nuclear fission as an energy source. Which city caused less acid rain?

A: Lake

Problem: Two large islands from the same archipelago were visited by explorers. Green island was home to most species of reptiles, while Blue island was favored by numerous species of birds and hardly any reptiles. Which island was inhabited by fewer turtles?

A: Blue

Problem: Two earth-like planets orbited the same star. The inhabitants of Earth I released greenhouse gases into the atmosphere. Earth II, however, was much more conscious about the environment and protected it from anthropogenic changes. Which planet didn't cause a reduction in wildlife population?

A:
Earth II