Remember that the formula for the area of a sector is:
[tex]A=\frac{\pi\cdot r^2\cdot\theta}{360}[/tex]Where:
• r, is the radius
,• Theta ,is the central angle (in degrees)
Using this formula and the data given,
[tex]\begin{gathered} A=\frac{\pi\cdot4^2\cdot45}{360} \\ \rightarrow A=2\pi \end{gathered}[/tex]