6. Samples of atmospheric air and exhaled air were analysed by four groups
of students for oxygen and carbon (IV) oxide content. The following are
the results, expressed in volumes per thousand:
(i) Amount of oxygen in atmosphere = 200
(ii) Amount of oxygen in exhaled air = 160
(iii) Amount of carbon (IV) oxide in atmosphere = 300
(iv) Amount of carbon (IV) oxide in exhaled air =41
Explain the difference in volume of each gas between the atmosphere and
the exhaled air.​