The amounts (in billions of dollars) the U.S. federal government spent on research and development for defense from 2010 through 2014 can be approximated by the model y = 0.5079t2 − 8.168t + 95.08 where t represents the year, with t = 0 corresponding to 2010?
(a) Use a graphing utility to graph the model.
(b) Find the average rate of change of the model from 2010 to 2014. Interpret your answer in the context of the problem?