Approximately what amount of $O_{2}$ reaches the tissues via $100 \ ml$ of blood (in $ml$)?

Which of the following has the highest affinity for hemoglobin?

In what form is the $CO_2$ released from body tissues into the blood transported?

$A$: $100 \; ml$ of venous blood contains $14.4 \; ml$ of $O_2$,meaning it is still $75\%$ saturated with oxygen under normal conditions.
$R$: About $4.6 \; ml$ of $O_2$,i.e.,$25\%$,diffuses from arterial blood into the tissues during resting conditions.

Hamburger phenomenon is also known as

With which part of $Hb$,$O_2$ molecules bind?