marginal cost curves etc

Use the following figure to answer the remaining questions below. You know from your lectures that MC = marginal cost; ATC = average total cost; AVC = average variable cost; AR = average revenue and MR = marginal revenue MC Maximum Profit Cost and Revenue AVC AR MR 5 6 8 9 10 11 Quantity b) At what quantity level will the AR curve intersects the quantity axis? (1 marks) c) What is the area of the total profit? (2 marks) d) Explain with the help of the above diagram that a profit maximising monopolist always overcharges and under produces than a firm operating in a perfectly competitive market structure and hence thereby creating a welfare loss