Problem 2.4 [5pts] (Fractional-knapsack problem) Suppose there are d precious minerals numbered 1,...,d. We want to select a fraction a; [0, 1] of the i-th mineral to fill a knapsack of capacity k (an integer between one and d). Compute the optimum fraction of each mineral that we must choose to put in the knapsack in order to maximize its total value given by - ;2;, where 1, 21,2...210 20 are the unit-prices of the d minerals