A company contains four employees available for work on the four machines. Only one employee can work on any one machine. The following table shows the cost of assigning each employee to each machine. You are required to assign employee to machine such that the total assignment cost is a minimum. E M 1 2 3 4 A 20 20 25 22 28 BCD 15 18 23 17 19 17 21 24 25 23 24 24