the president of a small manufacturing firm is concerned about the continual increase in manufacturing costs over the past several years. the following figures provide a time series of the cost per unit for the firm's leading product over the past eight years. year cost/unit ($) year cost/unit ($) 1 20.10 5 26.70 2 24.40 6 29.90 3 28.10 7 30.90 4 27.60 8 35.90 (a) construct a time series plot. what type of pattern exists in the data? the time series plot shows a horizontal pattern. the time series plot shows a seasonal pattern. the time series plot shows a nonlinear trend. the time series plot shows a linear trend. correct: your answer is correct. (b) use simple linear regression analysis to find the parameters for the line that minimizes mse for this time series. (round your answers to two decimal places.)