More than percent of earth is covered by water.

Altocumulus, altostratus, cirrocumuls, cirrostratus, cirrus, cumulonimbus, cumulus, nimbostratus, stratocumulus, stratus 8.) clouds with tallest vertical development 9.) low altitude clouds in solid layers that produce rain 10.) high altitude thin flat layers of clouds 11.) rain clouds that form under stable atmospheric conditions 12.) middle altitude clouds with globular appearance

The next best alternative given up when making a choice is called the a. opportunity cost b. comparative advantage c. primary objective d. negative consequence select the best answer from the choices provided. a b c d

Which water sources contribute to a river system? check all that apply. groundwater lakes rivers streams watersheds