What is Law of Demand?

What is Law of Demand? Prepare demand schedule based on Law of Demand.

The Law of Demand states that other factors remaining constant, the demand for a commodity expands with fall in its price and contracts with rise in its price.

An illustrated demand schedule is as follows:
The schedule shows extension of quantity demanded in response to decrease in own price of the commodity. Thus, demand expands from 100 to 150 units when price reduces from Rs 10 to RS 9 per unit.