The areas from which streams collect water are separated into , the borders of which are defined by local topographic highs.

Which of the following factors is not used to measure a country’s standard of living? a.) life expectancy b.)educational levels c.)divorce rates d.) gross income

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

Many rivers in central asia come from