Short$-$run supply and long$-$run equilibrium

Consider the competitive market for rhodium. Assume that no matter how many firms operate in the industry, every firm is identical and faces the same marginal cost $($MC$),$ average total cost $($ATC$),$ and average variable cost $($AVC$)$ curves plotted in the following graph.

The following graph plots the market demand curve for rhodium.

The following graph plots the market demand curve for thodium.

Use the orange points $($square symbol$)$ to plot the initial short$-$run industry supply curve when there are $10$ firms in the market. $($Hint: You can disregard the portion of the supply curve that corresponds to prices where there is no output since this is the industry supply curve.$)$ Next, use the purple points $($diamond symbol$)$ to plot the short$-$run industry supply curve when there are $20$ firms. Finally, use the green points $($triangle symbol$)$ to plot the short$-$run industry supply curve when there are $30$ firms.

If there were $20$ firms in this market, the short$-$run equilibrium price of rhodium would be $ dillililer pound. At that price, firms in this industry would $$ Therefore, in the long run, firms woul $q,$ the rhodium market.

Because you know that competitive firms earn $q,$ economic profit in the long run, you know the long$-$run equilibrium price must be per pound. From the graph, you can see that this means there will be firms operating in the rhodium industry in long$-$run equilibrium.

True or False: Assuming implicit costs are positive, each of the firms operating in this industry in the long run earns positive accounting profit.

$$ True

$$ False