A, b, and c-a. if heart and lungs are normal, the a-a gradient should not be a factor on oxygenation and there will be a linear relationship between pao2 and pao2.b. pao2 doesnt directly result in any change to the hemoglobin, and saturation is the important factor. pao2 only directly relates to the amount of o2 dissolved in the plasma (daltons law).c. the pao2 at the summit of mt. everest is only -6.74 (considering a normal co2 which would not exist if you were breathing 90 breaths per minute to try to keep up on o2).d. this is false as there is going to be some loss across the a-c membrane. so alveolar will always be higher than arterial.