Answer the question on the basis of the following data: $\begin{array}{cccccc}Quantity& MPof& MRPof& \text{Quantity of}& MPof& MRPof\\ ofLabor& Labor& Labor& Capital& Capital& Capital\\ 1& 15& \$45& 1& 8& \$24\\ 2& 12& 36& 2& 6& 18\\ 3& 9& 27& 3& 5& 15\\ 4& 6& 18& 4& 4& 12\\ 5& 3& 9& 5& 3& 9\\ 6& 1& 3& 6& 2& 6\end{array}$ Refer to the given data.If the prices of labor and capital are $9 and $15 respectively,at the profit-maximizing level,the firm's total output will be:

A) 38 units.
B) 60 units.
C) 64 units.
D) 27 units.

To find the profit-maximizing level of output, we need to find the point where the Marginal Revenue Product (MRP) of both labor and capital are equal to their respective prices.

For labor:
MP of labor / Price of labor = MRP of labor
15 / 9 = 1.67

Looking at the table, we see that the MRP of labor is equal to $27 when 3 units of labor are used. Therefore, the profit-maximizing level of labor is 3 units.

For capital:
MP of capital / Price of capital = MRP of capital
4 / 15 = 0.27

Looking at the table, we see that the MRP of capital is equal to $12 when 4 units of capital are used. Therefore, the profit-maximizing level of capital is 4 units.

Now, we can calculate the total output at the profit-maximizing level:

Total output = (MP of labor x units of labor) + (MP of capital x units of capital)
Total output = (9 x 3) + (4 x 15)
Total output = 27 + 60
Total output = 87

However, we need to check if this level of output is feasible given the constraint of labor input. At the profit-maximizing level, we are using 3 units of labor, which means we have 2 units of labor remaining. Looking at the table, we see that if we use 2 units of labor and 6 units of capital, we can produce an additional 3 units of output, for a total of 90 units.

Therefore, the best choice is C, with a total output of 64 units, since any level of output higher than 64 units is not feasible given the constraint of labor input.