What is the amount of $O_2$ supplied to tissues through every $100mL$ of oxygenated blood under normal physiological conditions?

Explanation:

In a normal person, about $15g$ haemoglobin is present per $100mL$ of blood.
$1g$ of hemoglobin combines with $1.34mL$ $O_2$
Therefore, $100mL$ oxygenated blood carries around $20mL$ of oxygen ($15\times 1.34=20.1$).
Out of $20mL$ of $O_2$ in every $100mL$ of oxygenated blood, $5mL$ of $O_2$ is supplied to the tissues under normal conditions.

Final answer:

$5ml$