(Transportation problem) There are two factories located one at place P and the other at place Q. From these locations, a certain commodity is to be delivered to each of the three depots situated at A, B and C. The weekly requirements of the depots are respectively 5, 5 and 4 units of the commodity while the production capacity" of the factories at P and Q are respectively 8 and 6 units. The cost of transportation per unit is given below :   How many units should be transported from each factory to each depot in order that the transportation cost is minimum. What will be the minimum transportation cost?