The Solution:
Given the profit function below:
To maximize profit, we have to differentiate the given function P with respect to n, and then equate to zero.
Solving for n, we get
Thus, the correct answer to part (a) is 85 thousand units of DVD.
Part (b)
We are required to find the maximum profit.
We shall substitute 85 for n in the given profit function.
Therefore, the maximum profit is 128.5 thousand of dollars.