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b) Because known models are not appropriate here, the following model is proposed to forecasting. The approach would be to calculate the increase from each month last year to each month this year, sum all 12 increases, and divide by 12 . The forecast for next year would equal the value for the same month this year plus the average increase over the 12 months of last year. c) Forecast demand for each month next year using the proposed model. The forecasts for the next year are (round your responses to the nearest whole numbers as needed)