Calculate the fractional saturation for hemoglobin when the partial pressure of oxygen is 76 mm Hg. Assume hemoglobin is 50% saturated with oxygen at a partial pressure of 22 mm Hg and that the Hill coefficient is 3.

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming