The following data report total, monthly U.S. book-store sales in millions of dollars from January 2016 to March 2019. (Go to https://www.census.gov/retail/Index.html#mrts, find "Monthly Retail Trade Report," then select "Time Series/Trend Charts" to find the data for the total U.S. bookstore sales.) Year Month 2016 2017 2018 2019 January $1, 548 $1,466 $1, 351 $1, 224 February 807 771 789 746 March 799 787 814 765 April 789 809 790 May 858 861 867 June 793 784 807 July 767 749 781 August 1, 604 1, 454 1, 444 September 1, 144 1, 877 1, 066 october 795 769 821 November 822 783 848 December 1, 336 1, 237 1, 339 Click here for the Excel Data File c. Which forecasting model is appropriate based on the data for the total U.S. bookstore sales? Appropriate model Regression analysisd. Evoluate a seasonally adjusted trend forecasting model. What is the MAD? (Round your answers to 4 decimal places.) Month Number $ Sales Perlod Trend Absolute (Millions) Index Forecast Error 1,548 807 2 799 3 789 858 5 793 767 7 1,604 8 1,144 9 795 10 822 11 1,336 12 1,486 13 771 14 787 15 809 16 861 17 784 18 749 19 1,454 20 1,077 21 769 22 783 23 1,237 24 1,351 25 789 26 814 27 790 28 867 29 807 30 781 31 1,444 32 1,086 33 821 34 848 35 1,339 36 1,224 37 746 38 785 39 MAD= e. What is the average monthly trend in book-store sales? (Negative amounts should be Indicated by a minus sign. Round your answer to 4 decimal places.) Average monthly trend in book store sales million dollars per monthf-1. What are the monthly indexes? (Round your answers to 4 decimal places.) Month Index 1 10 11 12 f-2. When are book sales the highest? When are book sales the highest f-3. When are book sales the lowest? When are book sales the lowestg. Predict book sales for the next 9 months. (Round your answers to 4 decimal places.) JEBA Month Forecast Sales 2019 April 2019 Mary 2019 June 2019 July 2019 August 2019 September 2019 October 2019 November 2019 December