Final answer:
Supply curves slope up from left to right, indicating a direct relationship between price and quantity supplied.
Step-by-step explanation:
Nearly all supply curves share a basic similarity: they slope up from left to right. This means that as the price of a product increases, the quantity supplied also increases, and as the price decreases, the quantity supplied also decreases.
For example, let's say the price of a gallon of milk rises from $1 to $2. As a result, the quantity supplied by dairies also increases from 500 gallons to 720 gallons.
Therefore, supply curves have a positive slope, indicating a direct relationship between price and quantity supplied.