Which of the following does not affect a population's size?
a. birth rate
c. death rate
b. exchange rate
d. migration rate

Nuclear experimentation is a major global issue that affects relationships between countries. describe why countries try to limit the testing of nuclear weapons.

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.

Name one type of data that h-r diagrams do not show.