Final answer:
Supply is the relationship between the price of a product and the quantity available at various prices, while quantity supplied is the amount available at a specific price. This is shown by an upward-sloping supply curve on a graph, where each point is a quantity supplied at a given price.
Step-by-step explanation:
The difference between supply and quantity supplied of a product is that supply refers to the whole relationship between the price of a product, such as milk, and the quantity of it that producers are willing and able to sell at each possible price over a certain period of time. Conversely, quantity supplied refers to the specific amount of the product that producers are willing and able to sell at a particular price.
On a graph, this relationship is depicted by the supply curve, which slopes upwards from left to right, representing the law of supply—that an increase in price typically results in an increase in the quantity supplied. A specific point on this curve represents the quantity supplied at a given price. If there were a change in conditions (like production costs or technology), the entire supply curve could shift, indicating a change in supply, whereas a move along the curve would indicate a change in the quantity supplied due to a price change.