Final answer:
The law of supply refers to the positive relationship between price and quantity supplied, stating that a higher price leads to a higher quantity supplied and a lower price leads to a lower quantity supplied. This law assumes that all other variables affecting supply are held constant.
Step-by-step explanation:
When economists talk about supply, they mean the amount of some good or service a producer is willing to supply at each price. Price is what the producer receives for selling one unit of a good or service. A rise in price almost always leads to an increase in the quantity supplied of that good or service, while a fall in price will decrease the quantity supplied. Economists call this positive relationship between price and quantity supplied the law of supply. The law of supply assumes that all other variables that affect supply are held constant.