Consider a well-known 0-1 Knapsack problem. Given a collection of n items with integral sizes w1,...,wn > 0 and values v1,...,vn > 0, and an integer knapsack capacity W > 0. The problem is to find integers w1,...,wn > 0 such that the total value is maximized, and it is known to be NP-Hard. As a possible heuristic, let's try the following greedy algorithm: sort items in non-increasing order of vi/wi and greedily pick items in that order. Show that this approximation.