Historical demand for a product is as follows: Demand April 64May 59June 74July 64August 79September 74a. Using a simple four-month moving average, calculate a forecast for October. (Round your answer to 2 decimal places.)b. Using single exponential smoothing with α = 0.30 and a September forecast = 55, calculate a forecast for October. (Round your answer to 2 decimal places.)c. Using simple linear regression, calculate the trend line for the historical data. Say the X axis is April = 1, May = 2, and so on, while the Y axis is demand. (Round your intercept value to the nearest whole number and slope value to 2 decimal places.)d. Calculate a forecast for October using your regression formula. (Round your answer to 2 decimal places.)