(Solved): (a) Construct a time series plot. What type of pattern exists in the data? The time series plot sho ...

(a) Construct a time series plot. What type of pattern exists in the data? The time series plot shows a linear trend. The time series plot shows a horizontal pattern. The time series plot shows a nonlinear trend. The time series plot shows a seasonal pattern. (b) Develop a linear trend equation for this time series to forecast the budget (in billions of dollars). (Round your numerical values to three dedmal places.)

(c) What is the forecast (in billions of dollars) for period 257 (Round your answer to two decimal places.)