Which natural wonder is actually a massive living organism, or life-form?
Nile River
Okavango Delta
Red Sea Reef
Sahara Desert

"spheres" is the name of the four subsytem

What school are you from and what state are you from?

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