Can someone simply explain linear regression? Can linear regression be automatically calculated in SPSS?

The following table gives the number of pints of type A blood used at Woodlawn Hospital in the past 6 weeks: Week Of August 31 September 7 September 14 September 21 September 28 October 5 a) The forecasted demand for the week of October 12 using a 3-week moving average = pints (round your response to two decimal places) b) Using a 3-week weighted moving average, with weights of 0.10, 0.30, and 0.60, using 0.60 for the most recent week, the forecasted demand for the week of October 12 = pints (round your response to two decimal places and remember to use the weights in appropriate order the largest weight applies to most recent period and smallest weight applies to oldest period.) c) If the forecasted demand for the week of August 31 is 360 and α = 0.20, using exponential smoothing, develop the forecast for each of the weeks with the known demand and the forecast for the week of October 12 (round your responses to two decimal places). Week Of August 31 September 7 September 14 September…

Chart and Regression analysis : What does the intercept predict?  X: C16 (number of cars on the sales lot) versus Y: C17 (cars sold per day) Equation: y=2.9x + 14.5 Slope:2.9 Intercept:14.5 Does the intercept mean the intercept is 14.5 means that the cars sold per day( Y) predicted number of cars on sale lot(X) to be 14.5, but this intercept has no meaning. So, I will not use to predict cars sold per day?