Answer:
60 players should be produced to minimize the marginal cost
Explanation:
Following the problem instructions, the marginal cost function is:

Then, to find the x players at
would has its minimum value, we have to find the first derivative as follows:

And the minimum value is determined when:

Then, we solve for x, and these would be the players produced to minimize the marginal cost:

That means at least 60 thousand players must be produced in order to minimize the marginal cost.