After winning the lottery, you decide to buy your own island. the island is located 1 km offshore from a straight portion of the mainland. there is currently no source of electricity on the island, so you want to run a cable from the mainland to the island. an electrical power sub-station is located 4 km from your island's nearest location to the shore. it costs $60,000 per km to lay a cable in the water and $40,000 per km to lay a cable over the land. (a) explain why we can assume the cable follows the path indicated in the picture; i. e., explain why the path consists of two line segments, rather than a weird curved path and why it is ok to assume the cable reaches shore to the right of the power station and the left of the island.