A time series model has been fit and checked with historical data yielding Yt=50+0.45 Y t-1+et Suppose at time t=60 the observation is Y60=57. A. determine forecasts for periods 61,62, and 63 from origin 60. B. suppose the observed value of Y61 is 59. Update teh forecast for periods 62 and 63. C. Suppose the estimate for the variance of the error term is s^2=3.2. Compute a 95% prediction interval about the forecast for period 61. Please answer ALL parts to this question and show work. PLEASE HELP. Thank you