The table shows the consumption C (in trillions of Btus) of geothermal energy and wind energy in the United States from 2004 through 2014. (Source: U.S. Energy Information Administration)

(a) Use a graphing utility to find a cubic model for the geothermal energy consumption data and a cubic model for the wind energy consumption data. Let t represent the year, with t = 4 corresponding to 2004.
(b) Use the graphing utility to graph the data and the two models in the same viewing window.

(c) Use the graph from part (b) to approximate the point of intersection of the graphs of the models. Interpret your answer in the context of the problem.
(d) Describe the behavior of each model. Do you think the models can accurately predict the consumption of geothermal energy and wind energy in the United States for future years? Explain.

Wind, C Year Geothermal, C DATA 2004 178 142 2005 181 178 181 264 2006 341 2007 186 546 192 2008 2009 200 721 923 2010 208 1168 2011 212 2012 212 1340 1601 2013 214 2014 215 1733 Spreadsheet at LarsonPrecalculus.com