. determine which demand curve entails negative economic profits. move the point labeled demand a to identify this curve. if the firm faces demand a, in the long run, you would expect the number of firms in the market to . b. determine which demand curve entails positive economic profits. move the point labeled demand b to identify this curve. if the firm faces demand b, in the long run, you would expect the number of firms in the market to . c. determine which demand curve illustrates zero economic profits. move the point labeled demand c to identify this curve. if the firm faces demand c, in the long run, you would expect the number of firms in the market to