please help i dont know why i got these two wrong

The manager of a travel agency has been using a seasonally adjusted forecast to predict demand for packaged tours. The actual and predicted values are as follows: Click here for the Excel Data File a. Compute MAD for the fifth period, then update it period by period using exponential smoothing with a=05, (Round your intermediate calculations and final answers to 3 decimal places.) Answer is complete but not entirely correct. b. Compute a tracking signal for periods 5 through 14 using the initial and updated MADs. (Negative values should be indicated by a minus sign. Round your intermediate calculations and final answers to 3 decimal places.) Answer is complete but not entirely correct