If a tree's radius is three feet and the average width of each annual ring is five inches, then what is the tree's estimated age? A. About six years
B. About seven years
C. About eight years
D. About nine years

Does the threat of global warming require international cooperation? why or why not?

What is the full meaning of rfid on computer

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.