Final answer:
The value of the marginal product of labor is 108y, and the profit-maximizing level of employment for a firm in a perfectly competitive labor market is approximately 0.000457.
Step-by-step explanation:
a. To determine the value of the marginal product at each level of labor, we need to calculate the partial derivative of the production function with respect to labor (x). Differentiating the production function p(x, y) = 108xy with respect to x, we get:
∂p/∂x = 108y
Thus, the value of the marginal product of labor is 108y.
b. In a perfectly competitive labor market, the profit-maximizing level of employment occurs when the market wage equals the marginal revenue product of labor (MRP). The MRP can be calculated using the derivative of the production function. In this case, since the production function is p(x, y) = 108xy, the MRP of labor is given by:
MRP = ∂p/∂x * Px = 108y * 243 = 26244y
Since the market wage is $12, we can equate the MRP to the wage to find the profit-maximizing level of employment:
26244y = 12
y = 12/26244 ≈ 0.000457
Therefore, the firm's profit-maximizing level of employment is approximately 0.000457.