10. the s-cargo shipping company calculates shipping charges using the linear model, y = 2.72x, where y is the cost in dollars and x is the weight of the package in pounds (1 ≤ x ≤ 9). use the linear model to compute the weight of a package with a shipping cost of $21.76. round to the nearest hundredth of a pound, if necessary. 11. two cars are 270 miles apart and travel toward each other on the same road. they meet in 3 hours. one car travels 2 mph faster than the other. what's the average speed of each car? 12. a line contains the point (4, 5) and is perpendicular to a line with a slope of . write an equation of the line satisfying the given conditions. write the answer in slope-intercept form. 13. solve the equation: 6 – 3(–2 – 4x) = 2(3(x – 4) + 7) 14. a freight train and a passenger train leave a rail yard at the same time and travel on parallel tracks. the passenger train travels 6 mph faster than the freight train. the combined distance traveled after 2 hours is 100 miles. what's the average speed of each train?