4. An oil rig lies 20 km off the coast of Newfoundland. A town lies 80 km along the coast from the nearest point on land to the rig. A pipe is to be drilled from the rig to the town. The cost per km of the pipe under water is $2.5 million, but on land is $1.5 million. Find the route that results in the cheapest pipeline, and determine that lowest cost