There are continents on the earth.
a. seven
b. four
c. six
d. nine

Which revelation resulted from the observation of the spectrum of different galaxies? a. there were more galaxies whose spectrum was blueshifted b. there were no galaxies whose spectrum was redshifted c. there were more galaxies whose spectrum was redshifted d. there were no galaxies whose spectrum was blueshifted

The world wars of the twentieth century immediately led to a. the establishment of a communist bloc in eastern europe b. the urbanization of europe’s societies c. an emphasis on humanism d. an emphasis on ties to greek and roman societies select the best answer from the choices provided. a b c d

Where the main factor that enabled the growth of cities and civilizations was the existence of