Why are prices described as a no-cost alternative when allocating scarce resources?

Needed fast 15 points the process of natural selection favors certain characteristics in organisms, while it selects against other characteristics. what would happen if there was zero variation between all of the organisms on earth? a.organisms would evolve to increase variety b.natural selection would operate faster c.less food would be available d.evolution through natural selection would not occur

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

Me answer as many as you can what percentage more of water is used to provide us with electricity versus for irrigation? do we use more freshwater in our homes or to provide us with electricity?