Answer:
1. Head, neck, upper limb, thorax - super vena cava - top of the right atrium.
2. Lower limb - inferior vena cava - bottom of the right atrium.
Explanation:
The Heart pumps the oxygen-rich blood to the different parts of the body to Otake oxygen and nutrients to these organs and then takes the oxygen-poor blood returns from the body to the heart.
The two major vessels that return oxygen-poor blood to the heart are 1. superior vena cava (SVC) that drainages Head, neck, upper limb, thorax and terminate at top of the right atrium, and 2. inferior vena cava (IVC), Lower limb and terminate at bottom of the right atrium.
1. Head, neck, upper limb, thorax - super vena cava - top of the right atrium.
2. Lower limb - inferior vena cava - bottom of the right atrium.