The Rainbow Clothing (RC) company owns manufacturing facilities in three towns (W, Y and Z), which distributes to three retail clothing shops in three other cities (A, B and C). The following table summarises factory availability, projected store demand and unit transport costs.

FLOW	A	B	C	FACTORY
W	8	6	6	70
X	12	14	12	100
Y	16	4	10	100
DEMAND				270

a) Formulate an initial feasible solution for Rainbow's transportation problem.

b) What is the cost of the initial solution?

c) Use the stepping-stone method to find the optimal solution.