The table below provides employment and labour force data for a small economy over a 3-month period. V Stock of Unemployment Stock of Stock of outside the Total Population Employment Labour Force Sept. 1 160,000 2,540,000 300,000 3,000,000 Oct. 1 160,000 2,485,000 355,000 3,000,000 Nov. 1 160,000 2,430,000 410,000 3,000,000 a. What is the unemployment rate on September 1, October 1, and November 1? b. Explain why the unemployment rate changes even though the stock of unemployment remains stable. c. Provide a likely explanation for the change in this economy's labour force. In this case, is the unemployment rate an accurate measure of the amount of slack (excess supply) in the labour market? a. The unemployment rate on September 1 is %. (Round your response to two decimal places.)