Answer
$\approx \$21,879.11$
Work Step by Step
Let's use a geometric sequence $\{a_n\}$ to model the salary at the beginning of the $n$th year:
$a_1=18,000$
$r=1+0.05=1.05$
Determine $a_5$ using the formula:
$a_n=a_1r^{n-1}$
$n=5$
$a_5=18,000(1.05)^4\approx 21,879.11$
