4. a) Suppose that a provincial government collects income tax revenues using a linear income tax schedule. A taxpayer who has a zero income in a given year receives a $500 as a living allowance from the government. If a taxpayer who has an annual income of $30,000 pays $4000 in taxes, what is the marginal tax rate? Draw the linear income tax schedule on a diagram. Is the tax schedule regressive? Justify your answer. (2.5 marks) b) Using a simple economic model, explain the factors that will reduce the level of tax evasion. Use a suitable diagram(s) to illustrate. Briefly discuss the strengths and shortcomings of the model. (2.5 marks)