Need only algorithm

Let us consider a long, quiet country road with houses scattered very sparsely along it. We can picture the road as a long line segment with an eastern endpoint and a western endpoint. Further, let us suppose that despite the bucolic setting, the residents of all these houses are avid cell phone users. You want to place cell phone base stations at certain points along the road, so that every house is within four kilometers of one of the base stations. () Devise an efficient algorithm that achieves the goal, using as few base stations as possible. (ii) Show that the solution delivered by your proposed algorithm is optimal. (ii) Analyze the time complexity of your proposed algorithm