Trade encourages the spread of-
O
People
Ideas
O
Goods
All of the above

Characteristics of substance farming include all of the following except

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.

What is the approximate chemical composition of the solar nebula?