Answer: Demand curve and Demand schedule
Explanation:
The demand curve is a graphical representation that shows the relationship that exist between the price of a product and the quantity demanded over a period of time. The price will be on the left vertical axis while the quantity demanded for the good will be on the horizontal axis.
The demand curve moves downward from the left to the right thereby expressing the law of demand which states that when the price of a good increases, the quantity demanded decreases vice versa.
A demand schedule is a table that shows the quantity demanded of a commodities or service at different prices. The demand schedule is usually made up of two columns with the first column listing the price of a commodity and the second column listing the quantity demanded of the product. It creates a visual representation when it's used in drawing the demand curve.