Consider a modification of the original RedBrand problem where there are N plants, M warehouses, and L customers. Assume that the only allowable arcs are from plants to warehouses and from warehouses to customers. If all such arcs are allowable—all plants can ship to all warehouses and all warehouses can ship to all customers—how many changing cells are in the spreadsheet model? Keeping in mind that Excel’s Solver can handle at most 200 changing cells, give some combinations of N, M, and L that will just barely stay within Solver’s limit.