Poor irri 3. Most of the population of the Arabian Peninsula lives
a. in the Rub' al-Khali.
b. along the coasts of the Persian Gulf and the Gulf of Oman.
c. along the coasts of the Persian Gulf and the Red Sea.

What is the result of the greenhouse effect? a. heat is deflected from the atmosphere. b. heat is released from the atmosphere. c. heat is kept in the atmosphere. d. plants are able to grow in the tropics where the air is the heaviest.

Which of the following is not a challenge to instituting sound global environmental policies? a. most changes are inexpensive and easy to implement. b. elected leaders who support unpopular environmental issues often are not re-elected. c. economic considerations outweigh environmental ones in many societies. d. there is no way to enforce international environmental agreements.

How does central place theory explain patterns in the size and distribution of cities?