Chapter 5.1, Problem 81E

Cost function. The marginal average cost of producing x smart watches is given by

     $\begin{array}{cc}\overline{C^{\prime }}\left(x\right)=-\frac{5,000}{x^2}& \bar{C}\end{array}(100)=250$

where $\bar{C}\left(x\right)$ is the average cost in dollars. Find the average cost function and the cost function. What arc the fixed costs?