In mammals,how much $CO_2$ is transported as bicarbonates of sodium and potassium in the blood?

Haemoglobin $(Hb)$ is a

The haemoglobin of a human foetus:

Given below are two statements.
Statement $I$: Carbonic anhydrase enzyme is found in $RBCs$ and is absent in plasma.
Statement $II$: The rate of formation of carbonic acid is very high inside $RBCs$ than in plasma.
In light of the above statements, select the correct answer from the options given below.

Every $100 \ ml$ of oxygenated blood can deliver around $............$ of $O_2$ to the tissues under normal physiological conditions. (in $ml$)

What is true about $RBCs$ in humans?