A concrete company transports concrete from three plants, 1, 2 and 3, to three construction sites, A, B and C. The plants can supply the following quantity of concrete (in tons) per week: Plant Supply(Capacity)
1 300
2 300
3 100

The requirements of the sites, in number of tons per week, are:

Construction site Demand(requirment)
A 200
B 200
C 300

The cost of transporting I ton Of concrete from each plant to each site is shown in the table below (in dollars per ton).

From A B C
1 4 3 6
2 7 5 9
3 4 5 5

How much concrete should the company ship from each plant to each construction site to fill the demand while minimizing the transportation cost?
a. List and explain carefully what the decision variables are?
b. Write out the objective function.
c. Write out the constraints.

As a result of a labeling mistake at the chemical factory, a farmer accidentally sprays weedkiller rather than fertilizer on half her land. as a result, she loses half of her productive farmland. if the property of diminishing returns applies to all factors of production, she should expect to seea. a decrease in the marginal productivity of her remaining land and an increase in the marginal productivity of her labor. b. an increase in the marginal productivity of her remaining land and an increase in the marginal productivity of her labor. c. an increase in the marginal productivity of her remaining land and a decrease in the marginal productivity of her labor. d. a decrease in the marginal productivity of her remaining land and a decrease in the marginal productivity of her labor.