Mountain climbers carry bottled oxygen when at very high altitudes.
(a) Assume that a mountain climber uses oxygen and does work at twice the rate for climbing 116 stairs/mm (1.96 L/min, 685 W), because of low air temperature and winds. Calculate how many liters of oxygen a climber would need for 6.5 h of climbing. (Note that only 40% of the inhaled oxygen is utilized and the rest is exhaled. Also note that your answer is in liters at sea level.)
(b) How much useful work does the climber do if he and his equipment have a mass of 94.0 kg and he gains 650 m of altitude?
(c) What is his efficiency for the 6.5 h climb?