The law of sines can be expressed as seen below:
[tex]\frac{a}{\sin A}=\frac{b}{\sin B}=\frac{c}{\sin C}[/tex]Applying that to triangle we were given we obtain:
[tex]\begin{gathered} \frac{3}{\sin38}=\frac{2.5}{\sin x} \\ 3\cdot\sin x=2.5\cdot\sin 38 \\ \sin x=\frac{2.5\cdot\sin 38}{3} \\ x=\sin ^{-1}(\frac{2.5\cdot\sin 38}{3})_{} \end{gathered}[/tex]So the first box is 2.5
The second box is 38
The third box is 3.