Unit Shipping Cost to Distributor in Plants Tacoma San Diego Dallas Denver St. Louis Tampa Baltimore Macon $2.50 $2.75 $1.75 $2.00 $2.10 $1.80 $1.65 Louisville $1.85 $1.90 $1.50 $1.60 $1.00 $1.90 $1.85 Detroit $2.30 $2.25 $1.85 $1.25 $1.50 $2.25 $2.00 Phoenix $1.90 $0.90 $1.60 $1.75 $2.00 $2.50 $2.65 Demand 8,500 14,500 13,500 12,600 18,000 15,000 9,000 Sentry wants to determine the least expensive way of manufacturing and shipping locks from its plants to the distributors. Because the total demand from distributors exceeds the total production capacity for all the plants, Sentry realizes it will not be able to satisfy all the demand for its product but wants to make sure each distributor will have the opportunity to fill at least 80% of the orders received. a. Create a spreadsheet model for this problem and solve it. b. What is the optimal solution