For the data in Problem 28, use the results of the regression equation to estimate the slope and intercept of the series at the end of June. Use these numbers as the initial values of slope and intercept required in Holt’s method. Assume that a 5 .15, b 5 .10 for all calculations.

a. Suppose that the actual number of visitors using the park in July was 2,150 and the number in August was 2,660. Use Holt’s method to update the estimates of the slope and intercept based on these observations.

b. What are the one-step-ahead and two-step-ahead forecasts that Holt’s method gives for the number of park visitors in September and October?

c. What is the forecast made at the end of July for the number of park attendees in December?