One fuel-saving tip is to observe the speed limit. A vehicle's gas mileage generally decreases significantly for speeds over 50mph, as suggested by the data below. F(x) 40 35 F(x) = 0. 000095x3 - 0. 0225x2 + 1.421x + 3.26 50 (in miles per hour) Fuel Economy 25 20 15 10 5 20 40 60 80 Speed (in miles per hour) The polynomial function F(x) = 0.000095x3 - 0.0225x2 + 1.421x + 3.26 can be used to estimate the fuel economy, in miles per gallon (mpg), for a particular vehicle traveling x miles per hour (mph). a) What is the graph mileage for this vehicle at 60mph? What is the gas mileage for 80 mph? c) Estimate F (75)