What numbers are Pakistan, Afghanistan, Nepal, Bhutan and Sri Lanka

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

Which environment would most likely not contain fossils? a a thick deposit of cracked, dried mud b sediment deposited in a sandy river bed c intrusive rock formed from cooled magma d layers of sand accumulated for a century

Which factors add to the greenhouse effect and are caused by human activities?