3. a) Suppose demand for good X is given by QD = 900- p/2 where p is the price and QD the quantity demanded. Supply is given by QS = p/4. Suppose 60 $ tax is imposed on each unit of X that is purchased. What is the burden of the tax? Explain the key factors that determine the incidence of the tax.

b) Describe the main differences between partial and general equilibrium analysis in the context of examining tax incidence.