A company that sells musical instruments has been in business for five years. During that time, sales of pianos increased from 13 units in the first year to 76 units in the most recent year. The firm's owner wants to develop a forecast of piano sales for the coming year. The quarterly sales data follow. Year Quarter 1 | Quarter 2 Quarter 3 Quarter 4 Total Yearly Sales 13 14 28 11 5 16 35 12 9 7 22 50 18 10 13 35 76 (a) Deseasonalize the data. (Round your answers to four decimal places.) Year Quarter Sales Adjusted Seasonal Deseasonalized Index Sales 5 1.2940 1.5451 2 0.6097 8.2010 3 0.4909 9.760 4 1.6054 1.2456 1.2940 4.8364 2 0.6097 6.5816 3 0.4909 9.7608 4 14 1.6054 4.3600 11 1.2940 3.8647 2 3 0.6097 9.8393 3 0.4909 7.3181 16 1.6054 5.6053 12 1.2940 13.9083 2 9 0.6097 4.7591 W 7 0.4909 17.0790 4 22 1.6054 9.9659 1 18 1.2940 17.0077 2 10 0.6097 16.4001 3 13 0.4909 31.7190 35 1.6054 21.8057 TE Use the deseasonalized time series to identify the trend. (Let t = 1 denote the time series value in quarter 1 of year 1; t = 2 denote the time series value in quarter 2 of year 1; ... and : = 20 denote the time series value in quarter 4 of year 5. Round your numerical values to two decimal places.) (b) Use the results of part (a) to develop a quarterly for forecast for quarter next year based on trend. (Round your answers to two decimal places.) forecast for quarter 2 forecast for quarter forecast for quarter 4 forecast for quarter 1 (c) Use the adjusted seasonal indexes given in part (a) to adjust the forecasts developed in part (b) to account for the effect of season. (Round your answers to one decimal place.) forecast for quarter 2 forecast for quarter 3 forecast for quarter 4