please without using excel ,by hand

Problem 3 A company distributes fertilizers to various garden shops. The company must base its quarterly production schedule on a forecast of how many tons fertilizer will be demanded from it. The company has gathered the following data for the past 3 years from its sales records: Q.1 - Compute a three-quarter moving average forecast for quarters 4 through 13 and compute the forecast error for each quarter. Q.2 - Compute a five-quarter moving average forecast for quarters 6 through 13 and compute the forecast error for each quarter. Q.3 - Comptive a weighted three-quarter moving average forecast, using weights of 0.5, 0.33, and 0.1. most recent, next most recent, and most distant data respectively. Then, compute the forecast error for each quarter. Q.4-Compare the forecasts developed in Q.1,2, and 3 using cumulative error and MAD