The mean annual salary for a sample of electrical engineers is \($86,500\), with a standard deviation of \($1500\). The data set has a bell-shaped distribution.

(a) Use the Empirical Rule to estimate the percent of electrical engineers whose annual salaries are between \($83,500\) and $89,500.

(b) The salaries of three randomly selected electrical engineers are $93,500,

\($85,600\), and \($82,750\). Find the z-score that corresponds to each salary.

Determine whether any of these salaries are unusual.