Use the formula of the area of a circle to find the area.
[tex]A=\pi\cdot r^2[/tex]Remember that the diameter is 2 times the radius, find the radius.
[tex]\begin{gathered} r=\frac{D}{2} \\ r=\frac{6}{2} \\ r=3 \end{gathered}[/tex]Once found the radius, estimate the area of the circle.
[tex]\begin{gathered} A=\pi\cdot3^2 \\ A=9\pi \\ A=28.27 \end{gathered}[/tex]The area of the circle is 28.27cm^2