Julio has been tracking the stock price of Computer Dudes, Inc. over the 40 days since it started trading on the New York Stock exchange. He models
the stock price over the 40 days with the function p(z) = -0.000083z +0.0069z³ -0.165z2+z+3.70, where p(x) represents the stock price,
in dollars, on the xth day since the stock started trading.