The graph below shows a company's profit f(x), in dollars, depending on the price of pens x, in dollars, being sold by the company: graph of quadratic function f of x having x intercepts at ordered pairs negative 0, 0 and 10, 0. the vertex is at 5, 160 part a: what are the x-intercepts and what do they represent in the context of the problem. what is the maximum value of the graph and what does it represent in the context of the problem? (6 points) part b: what is an approximate average rate of change of the graph from x = 5 to x = 8, and what does this rate represent? (4 points) (10 points)