Final answer:
Economists use economic models and supply and demand curves to deal with the problem of changing factors in a market.
Step-by-step explanation:
When analyzing a market, economists deal with the problem that many factors are changing at the same time by using economic models. These models help analyze market behavior and predict outcomes by representing the market with supply and demand curves. By studying these curves, economists can understand how prices reach a market equilibrium and determine the stability of prices in the market.