Suppose moviegoers' demand functions are the same as in Worked-Out Problem 18.2, but marginal cost is instead

Question:

Suppose moviegoers' demand functions are the same as in Worked-Out Problem 18.2, but marginal cost is instead $3 per ticket (instead of $2 per ticket, as in the Worked-Out Problem). What prices will the monopolist set when she can discriminate and when she can cannot? How will discrimination affect her profit?