Pepsin, a common enzyme found in the stomach, is the most active between pH values a pH of about 3.5 it becomes completely inactive.

Number and variety of living organisms includes genetic, species, and ecological types

What causes eclipses? check all that apply. earth's rotation on its axis moon's shadow covering the sun earth's shadow covering the moon earth's orbit and moon's orbit occasionally aligning the moon and sun's gravity pulling in the same direction

Which factor is difficult to assess in a cost-benefit analysis