[tex]The \ area \ of \ the \ curved \ surface \ of \ a \cone :\\\\A= \pi rl \\ \\ Where: \\ radius : \ r= 7 \ feet \\ height: \ h= 28 \ fett \\ slant \ height : \ l= ?[/tex]
[tex]use \ the \ Pythagorean \ Theorem \\\\ l^2=h^2+r^2 \\l^2=28^2+7^2\\l^2=784+49\\l^2=833 \\l=\sqrt{833}=\sqrt{49\cdot 17}=7\sqrt{17}\ feet[/tex]
[tex]A=\pi\cdot 7\cdot 7\sqrt{17} =49\sqrt{17} \pi \ ft^2\\\\ \pi=3.14 \\\\A\approx 49\cdot 4.12\cdot 3.14 \approx 633,9 \ ft^2[/tex]
[tex]Volume \ of \ a \ Cone : \\\\ V=\frac{1}{3}\pi r^2h\\\\ V=\frac{1}{3}\pi \cdot 7^2 \cdot 28=\frac{1}{3}\pi \cdot 49 \cdot 28= 457,33 \pi \ ft^3\\\\V\approx 457,33\cdot 3.14 \approx 1436.02 \ ft^3[/tex]
