28. Regression analysis was used to estimate the following seasonal forecasting equation: St=124+18Dtl46Dtz28Dti+2.5t Dtl is a dummy variable that is equal to one in the first quarter and zero otherwise; D22 is a dummy variable that is equal to one in the second quarter and zero otherwise; and D13 is a dummy variable that is equal to one in the third quarter and zero otherwise. Forecast the level of sales in the fourth (4th) quarter of time period 10. (A) 149 (B) 180 (C) 205 (D) None of the answers is correct. 29. Regression analysis was used to estimate the following linear trend equation: St=26+10t The ratio-to-trend method was used to calculate 0.75,0.95,1.10, and 1.20 , which are the seasonal adjustment factors for quarters 1,2,3, and 4 , respectively. Use this information to determine the forecast value for the third (3rd) quarter of time period 7. (A) 105.6 (B) 48.4 (C) 45.1 (D) None of the answers is correct. 30. Regression analysis was used to estimate the following seasonal forecasting equation: St=124+18Dt146Dt228Dt3+2.5t Dt1 is a dummy variable that is equal to one in the first quarter and zero otherwise; D2 is a dummy variable that is equal to one in the second quarter and zero otherwise; and D13 is a dummy variable that is equal to one in the third quarter and zero otherwise. Forecast the level of sales in the second (2nd) quarter of time period 10. (a) 195 (b) 170 (c) 103 (d) None of the answers is correct