Question 4.1. What kind of barriers to entry have allowed Australia Post to continue as a monopoly in providing postal services for standard mail in Australia? Explain your answer. [2 Marks] Question 4.2. What are the arguments against and for such a monopoly? Illustrate your answer with a diagram. [4 Marks] Question 4.3. Australia Post maintains a monopoly in the standard- mail market in Australia, in that it controls both the infrastructure and the retail side of the industry. How could it be losing money? [2 Marks]