Final answer:
A downward-sloping demand curve illustrates the law of demand, showing that as the price of teeth-whitening kits increases, the quantity demanded decreases, and as the price decreases, the quantity demanded increases. The options that correctly represent these principles are: a) as price increases, quantity demanded decreases, and c) as price decreases, quantity demanded increases.
Step-by-step explanation:
A downward-sloping demand curve for a product like teeth-whitening kits shows that there is a specific relationship between the price of an item and the quantity of it that consumers are willing to purchase at that price. Specifically, the law of demand is demonstrated by two main principles on this curve:
- As price increases, quantity demanded decreases.
- As price decreases, quantity demanded increases.
This means the correct options for a multiple select question would be:
- a. As price increases, quantity demanded decreases.
- c. As price decreases, quantity demanded increases.
In economic terms, when we talk about the demand curve shifting, an increase in demand signifies a rightward shift, showing that at every price level, the quantity demanded has increased, while a decrease in demand shifts the demand curve to the left.