PLEASE show in Excel so I can learn! Thank you!

A company has three warehouses that supply four stores with a given product. Each warehouse has 30 units of the product. Stores 1, 2, 3, and 4 require 20, 25, 30, and 35 units of the product, respectively. The per unit shipping costs from each warehouse to each store are given in the following table. (Let X_ij represent the number of units that flow from warehouse i to store j for i = 1, 2, 3 and j = 1, 2, 3, 4.)

	Store
Warehouse	1	2	3	4
1	7	6	8	6
2	4	8	6	6
3	5	5	4	4

(a)

Draw the network representation of this problem. What kind of problem is this?

This is a minimal spanning tree problem.This is a maximal flow problem. This is a transshipment problem.This is a transportation problem.This is a shortest path problem.

(b)

Formulate an LP model to determine the least expensive shipping plan to fill the demands at the stores.

MIN:

Subject to:

Flow from Warehouse 1:

Flow from Warehouse 2:

Flow from Warehouse 3:

Flow to Store 1:

Flow to Store 2:

Flow to Store 3:

Flow to Store 4:

X_ij 0

(c)

Solve the problem using Solver.

(X₁₁, X₁₂, X₁₃, X₁₄, X₂₁, X₂₂, X₂₃, X₂₄, X₃₁, X₃₂, X₃₃, X₃₄) = ( )

(d)

Suppose that shipments are not allowed between warehouse 1 and store 2 or between warehouse 2 and store 3. What is the easiest way to modify the spreadsheet so that you can solve this modified problem?

Assign arbitrarily small costs such as $0.01 to the arcs representing these flows.Assign arbitrarily large costs such as $999 to the arcs representing these flows.

(e)

What is the optimal solution to the modified problem?

(X₁₁, X₁₂, X₁₃, X₁₄, X₂₁, X₂₂, X₂₃, X₂₄, X₃₁, X₃₂, X₃₃, X₃₄) = ( )