An oligarchy can be both a monarchy and an anarchy at the same time true or false?

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

Find the coordinates of a if b(-9,-10) is the midpoint of ac and c has the coordinates of (-1,9)

The covers all of earth like a thin shell,but it is not a solid sheet of material.it is broken up into several large sections and many smaller ones. fill in the blank.