2. Most of a star's "life" is spent as a what
star.

How can health insurance increase life expectancy

Which evidence is most likely used to indicate the beginning of solar system formation? a. materials combined to form a mass. b. materials were pulled together by gravity. c. water condensed and collected to form oceans. d. different species of microorganisms lived on earth.

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.