Write the Word or Phrase That Best Completes Each Statement $$W=\frac{S(S-A)}{A}$$

Essay

Write the word or phrase that best completes each statement or answers the question
-The average waiting time in a line before getting served is given by
$$W=\frac{S(S-A)}{A}$$
where $\mathrm{A}$ is the average rate that people arrive at the line and $\mathrm{S}$ is the average service time. At a certain bank, the average service time is 4 minutes. By sketching a graph of the equation on the interval $(0,4]$ , answer the following questions. What happens to $W$ when A is close to zero? Why does this make sense? What feature of your graph gives this information?