Persons living at high altitude will have

Which of the following statement$(s)$ is/are correct?
$(a)$ High concentration of carbonic anhydrase in RBCs.
$(b)$ High concentration of carbonic anhydrase in blood plasma.
$(c)$ Every $100 \ ml$ of deoxygenated blood delivers approximately $4 \ ml$ of $CO_2$ to the alveoli.
$(d)$ $20-25\%$ of $CO_2$ is carried by hemoglobin as oxyhemoglobin.

Which of the following is functional for protection against the environmental abiotic factor of temperature or for thermoregulation of the living body during winter or summer?

The total pulmonary ventilation is related to the metabolic rate of the body as:

Describe the steps of respiration in short.

Statement-$I$: All the factors in our body are favourable for the diffusion of $O_2$ from alveoli to tissues and that of $CO_2$ from tissues to alveoli.
Statement-$II$: $A$ sigmoid curve is obtained when the percentage saturation of haemoglobin with $O_2$ is plotted against the $pO_2$.