(11) The Phillips curve for a particular economy is: t = Tit1 'l' ft + 2!: Suppose that 15' = 1/2, and that in period 0, inflation is 1 percent (1:0 = 1%). In period 1 only, there is an unexpected increase in the oil price so 21 = 0.04. Calculate inflation in periods 1, 2, 3 and 4 if the central bank counteracts the cost- push shock so the output gap is minus two percent in periods 2 and 3 and zero thereafter