The cost of fuel per kilometer for a truck travelling v kilometers per hour is given by the equaon 50 CM = i + . 150 17 What speed will result in the lowest fuel cost per kilometer? Hint, you should test the point to ensure that it is a minimum. Assume the driver is paid $53/h. What speed would give the lowest cost, including fuel and wages, for a 1 000 km trip? m A lifeguard at a public beach has 600 m of rope available to lay out a rectangular restricted swimming area using the straight shoreline as one side of the rectangle. If she wants to maximize the swimming area, what will the dimensions of the rectangle be? To ensure the safety of swimmers, she decides that nobody should be more than 55 m from the shore. What should the dimensions of the swimming area be with this added restriction