In a given market the supply curve is based on the following: producers an suppy at a price of 10 up to a quantity of 100. No more than 100 can be pplied. Producers will not supply if price is below 10. The demand curve QD = A -20p. . 1. Graph the supply curve and interpret it. 2. Now determine A such that the market "just exists" - this the smallest value of A such that an infinitesimal amount will be sold. You can use graphs to help with this; for example, graph the demand curve for a given guess at A and see whether or not the market exists. 3. Determine the range of values of A for which the market "maxes out" and the maximum feasible amount is sold.