Chapter 4.1, Problem 5ECP

A business has a cost function of $C=0.4x+8000$, where $C$ is measured in dollars and

$x$ is the number of units produced. The average cost per unit is given by

$\bar{C}=\frac{C}{x}=\frac{0.4x+8000}{x},x>0.$

a. Find the average costs per unit when $x =1000, x=8000,x =20,000,\text{ and} x=100,000.$

b. What is the horizontal asymptote of the graph of this function, and what does it represent?