A deep ocean trench exists where an ocean plate is cool and dense enough to sink beneath another plate.

The difference(s) between the grand canyon and valles marineris is/are: (a) the grand canyon was formed by water, but valles marineris was not. (a) valles marineris is much longer than the grand canyon. (c) valles marineris is much wider than the grand canyon. (d) valles marineris has large volcanoes near it. all of the above

In the developed world, women are increasingly more likely to delay childbirth until their mid- to late- twenties or long because

How does central place theory explain patterns in the size and distribution of cities?