Questions

Herodotus, a Greek author written the first history book in 5th century B.C.

Veins carries Blood back from the body parts to the Heart.

We know that The circulatory system of our body is a loop. The Heart is the pump, the arteries and their smaller branches (arterioles) carry oxygen rich blood all through your body and the veins and their smaller branches (venules) carry oxygen depleted blood and waste products back.

It is a collection of routers under the control of a single administrative authority and that uses a common Interior Gateway Protocol

The nervous system of the human brain consists of the central nervous system which has brain and the spinal cord and the peripheral nervous system which has perpheral, cranary, spinal nerves.