Answer
$39.2^\circ$
Work Step by Step
Using the definition of tangent of the angle A, we have
$$
\tan A=\frac{length \ of \ side\ opposite\ angle\ A}{length \ of \ side\ adjacent\ angle\ A}=\frac{2.62}{3.21}=0.8162
.$$
That is,
$$
\tan A= 0.8162 \Longrightarrow A=\tan^{-1} 0.8162=39.2^\circ
.$$
