You need to ship n packages across the country using trucks. each package i has a weight wi, and each truck can hold a total weight of m. you want to make the shipment using as few trucks as possible. more formally, given n packages with weights w1, , and numbers m and k, is there a way to ship the packages using ktrucks where the total weight carried by each truck is at most m? prove that this problem is np-hard. then, find a greedy algorithm that uses at most twice as many trucks as optimal. provide a proof.