manufacturing firm has four plants and wants to find the most efficient means of meeting the requirements of its three customers. The relevant information for the plants and customers, along with shipping costs in dollars per unit, are shown in the table below: Customer $($requirement$)$ Factory $($capacity$)$Customer $1(125)$Customer $2(150)$Customer $3(175)$ A$(100)$ $ $15$ $ $10$ $ $20$ B $(75)$ $ $20$ $ $12$ $ $19$ C $(100)$ $ $22$ $ $20$ $ $25$ D $(250)$ $ $21$ $ $15$ $ $28$ What is the minimum total cost?