The Metalco Company desires to blend a new alloy of 25 percent tin, 40 percent zinc, and 35 percent lead from several available alloys having the following properties: The objective is to determine the proportions of these alloys that should be blended to produce the new alloy at a minimum cost. Formulate a linear programming model for this problem. Let xi be the amount of Alloy i used for i=1,2,3,4,5. Maximize or minimize maximize minimize C=x1+x2+x3+x4+x5 subject to x1+x2+x3+x4+x5=(Tin)x1+x2+x3+x4+x5=(Zinc)x1+x2+x3+x4+x5=(Lead)