The answer is 25 degree, because when the sun is directly
overhead, its rays strike the earth at a 90 degree angle. The closer to 90
degrees the rays are, the more concentrated they are and the greater is the
heat they produce on the earth's surface. The solar heat reach the surface of
the earth becomes less intense as the angles of the rays decreases.
Areas near the North or South Pole, receive sunlight at a smaller angle, because of Earth’s spherical shape. At smaller angles, the sunlight is less intense because it spreads out over more area, and temperature are cooler, so is 25
the hormone erythroprotein increases the production of red blood cells when oxygen levels are low best supports teh statement taht hormones are involved in the regulation of homesstasis.
