The Tigasin Concrete Company has three plants in different locations and is presently working on three construction projects, each located at a different site. Weekly capacities and project requirements are as follows.

Plant Capacity

A 400

B 500

C 600

Project Requirement

1 700

2 450

3 350

The shipping costs from the plants to the projects are given in the following table:

Project 1 Project 2 Project 3

Plant A 12 6 13

Plant B 11 7 10

Plant C 10 9 8

Find a routing plan that minimizes total transportation cost.