Problem 12-22 (Algo) Given the model below: Period 1 2 3 4 5 6 7 9 10 11 Demand 110 140 170 130 130 130 150 170 170 160 200 02 90 90 45 95 95 price 50 63 47 64 51 es DRictureClick here for the Excel Data File a. Compute the forecast for period 12 using a causal regression model and assuming that all price for period 12 is 89. (Round regression coefficients and forecasts of demand to two decimal places.) Forecast for period 12 b. Create a graph of the gasoline sales and oil price data and include a line representing the regression model. In which period is gasoline sales least well predicted by oil price? What is the amount of this largest error? (Use your rounded regression coefficients and errors from Parta. Round your largest error answer to 2 decimals. Include the negative sign if that largest error is negative.) Largest errori in period