Consider the following data: Monthly Profit of a Gym: Month & Profit: Jan-12: 5800 Feb-12: 5553 March-12: 5094 April-12: 4797 May-12: 5215 June-12: 5718 July-12: 6719 Aug-12: 6208 Sept-12: 5936

Use Microsoft Excel or other software to create a scatter plot of the relationship between elevation and air density shown in the table below. Add a trend line fit of your choice to the plot and create an empirical model that predicts the density for a value of the elevation. Justify your choice of model fit to the data (i.e., explain what you did and why). Elevation (km) Density (kg/m3) 0 1.225 1 1.112 2 1.007 3 0.9093 4 0.8194 5 0.7364 6 0.6601 8 0.5258 10 0.4135 15 0.1948 20 0.08891 25 0.04008

U.S. Civilian Labor Force (thousands) Year Labor Force   Year Labor Force 2007 153,918   2012 155,628 2008 154,655   2013 155,151 2009 153,111   2014 156,238 2010 153,650   2015 157,957 2011 153,995   2016 159,640   1. Fit three trend models: linear, exponential, and quadratic. Which model would offer the most believable forecasts? 2. Make forecasts using the following fitted trend models for years 2017-2019. t          Exponential 11 12 13