The formula to find the volume of a cone is
[tex]\begin{gathered} V=\frac{1}{3}\pi r^2h \\ \text{ Where V is the volume,} \\ r\text{ is the radius of the circle of the base and } \\ h\text{ is the height of the cone} \end{gathered}[/tex]In this case, you have
[tex]\begin{gathered} r=h \\ \pi\approx3.14 \\ V=\frac{1}{3}\pi r^2h \\ 28.26mm^3=\frac{1}{3}(3.14)r^2(r) \end{gathered}[/tex]Now, you can solve the equation for r
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