An automotive engineer studied the effect of car weight in tons on fuel efficiency, which is measured in miles per gallon (mpg). The data from two cars in the study showed that a 2 ton car had a fuel efficiency of 37 mpg and a 2.5 ton car had a fuel efficiency of 34 mpg. Find a linear model that gives the fuel efficiency E (in mpg) of a car as a function of its weight w (in tons). Use the model to find the fuel efficiency (in mpg ) of a car that weighs 3 tons. mpg