A company is developing four network projects, and looking for the best shipping costs for category 6 network boxes, from suppliers A, B, C with a maximum supply capacity of 15, 25.5 respectively, per what the demand of project 1, is 5 boxes, project 2 and 3, is 15 boxes respectively and the fourth project needs 5 network boxes, the table of shipping costs are shown in the table. The project manager is required to determine the minimum costs for each project. P3 P2 $ A P1 $ 10 $ 12 $ B $ 7 $ 14 $ 10 $ 9 $ 16 P4 $ 11 $ 20 $ 18 C Use the northwest corner method to set the initial cost: To consider the exercise as good you must leave evidence of the entire procedure. Note: The model is not balanced, investigate how to proceed in this case