A company wishes to develop a linear program model that will satisfy demand at a minimum cost. Using the data in Table 9.2 and Table 9.3, which of the following statements contains the correct formulation of the objective function for this problem?

a) min z = 200(H1 + H2 + H3 + H4) + 350(F1 + F2 + F3 + F4)

b) min z = 200(H1 + H2 + H3 + H4) + 350(F1 + F2 + F3 + F4) + .30(I1 + I2 + I3 + I4)

c) min z = 200(H1 + H2 + H3 + H4) + 350(F1 + F2 + F3 + F4) + .30(I1 + I2 + I3 + I4) + P1 + P2 + P3 + P4

d) min z = 200(H1 + H2 + H3 + H4) + 350(F1 + F2 + F3 + F4) + .30(I1 + I2 + I3 + I4) + W1 + W2 + W3 + W4

Table 9.2

Quarter   Forecast

1                7,000

2              15,000

3              40,000

4              38,000

Hiring Cost $200 per worker

Firing Cost $350 per worker

Inventory Carrying Cost $.30 per unit

Production Per Employee 500 units per/qtr

Beginning Work Force 50 workers

Table 9.3

Decision Variables

Ht # workers hired for period t

Ft # workers fired for period t

It # units in inventory at end of period t

Pt # units produced in period t

Wt Workforce size in period t