14. (9 pts) The smoothed time series curves below both show seasonal components. Time is measured in months.~ a) Write a 1" order autoregressive model you would use to analyze the data underlying the smoothed curve below.~ 60 100 120 Time b) Write a 1" order autoregressive model you would use to analyze the data underlying the smoothed curve below.~ t c) Describe a simple technique (not one found on Google) you would use to estimate o (phi) in the 1* order autoregressive model you specified in part a) above using the observations from the data underlying the smoothed curve shown in part a