Questions

Magnetism in materials is due to circular motion of electrons.

The main difference lies in the motive of the two parties. The main motive of the hedger is to hedge(minimize) the risk from the occurence of some events. 

The motive of the speculator is to gamble in the market in order to make the profit by buying/selling the derivative products.

Romans (753 BC - AD 410) began public health and sanitation systems.

Romans established the first public health and sanitation systems by building sewers and aqueducts.

They also treated diseases with diet, exercise and meditation.

Oxygen is transported throughout the body via hemoglobin in the red blood cells. Hence, most of the oxygen transported by the blood is bounded to hemoglobin.

Pascal's law is a principle in fluid mechanics that states that a pressure change occurring anywhere in a confined incompressible fluid is transmitted throughout the fluid such that the same change occurs everywhere.

This principle is stated mathematically as: P= P + rgh