1. (15 points) The following data are the sales data for an air filter at an auto parts store on East Avenue, which were collected each month from January to June this year. Month January February March April May June Air filter Sold (box) 12 14 18 20 15 24 (a) Compute three months moving averages for the sales time series. What would be your forecast for July sale? (b) Compute the Exponential Smoothing series of the sales data using alpha=0.15. What would be your forecast sale of July based on exponential smoothing? 1(c) Compute the linear trend line for the sales data