for 9)
[tex]\bf \textit{volume of a cylinder}=V=\pi r^2 h\qquad
\begin{cases}
h=height\\
r=radius=\frac{diameter}{2}\\
--------------\\
diameter=12\\
r=\frac{12}{2}=6\\
volume=1018
\end{cases}
\\\\
\\
1018=\pi \cdot 6^2\cdot h\impliedby \textit{solve for "h"}[/tex]
for 10)
[tex]\bf \textit{volume of a cone}=V=\cfrac{\pi r^2 h}{3}\qquad
\begin{cases}
h=height\\
r=radius\\
--------------\\
h=20\\
volume=2094
\end{cases}
\\\\
\\
2094=\cfrac{\pi \cdot r^2\cdot 20}{3}\impliedby \textit{solve for "r"}[/tex]
now for 11)
[tex]\bf \textit{volume of a sphere}=V=\cfrac{4}{3}\pi r^3\qquad
\begin{cases}
r=radius\\
---------\\
volume=4189
\end{cases}
\\\\
\\
4189=\pi \cdot r^3\impliedby
\begin{array}{llll}
\textit{solve for "r"}\\
\textit{now, the diameter is twice the radius}\\
\textit{so, the diameter will be }2r
\end{array}[/tex]
