Problem: John and Keith are neighbors. They have been pondering about how to communicate with each other in a doomsday scenario when all the electronic devices would be useless. They connected their houses with three ducts. One of the ducts is filled with air; they called it channel A. Another duct is filled with water; they called it channel B. And the last duct is filled with iron; they called it channel C. They can now transmit sound with these channels of communication; in case, disaster strikes. How much faster would be channel C than channel B in m/s, 3640 m/s or 3600 m/s?

A: 3640 m/s

Problem: Two coastal communities on two neighboring gulfs took different approaches to bringing more money into the local economy. Davin village continued with commercial fishing and agriculture, while the village of Forx decided to mine sand from the nearby dunes, because it was very profitable. They did not think about the effect it would have on the environment. Which village was more thoughtful about the environment?

A: Davin

Problem: 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 increased infiltration to prevent erosion?

A: Gary

Problem: Adam was playing tag football when one of his friends tagged him a bit too hard and caused him to tumble and fall. He noticed when he fell, he got a pretty bad cut in his knee. He decided to ignore the injury for now and keep playing. Later when he got home he realized the area of the cut was warm and swollen Will the blood vessels near Adam's injury have expanded or contracted?

A:
expanded