Question

Find the missing measures for a right circular cone.

Answer 1

Lateral area of cone=pi r sqrt(h^2+r^2), h=?, r=?
l=4
h^2=16-r^2
\[\pi r \sqrt(h^2+r^2)=8\pi\]
\[ r\sqrt16-r^2+r^2 =8\]
4r=8
r=2
\[h=\sqrt12=2\sqrt3\]
total area=lateral area+ surface area of base=8pi+4pi=12pi

Volume=1/3pir^2h
\[=(1/3)\pi*4*2\sqrt3\]
\[=\frac{8\pi}{\sqrt3}\]

Answer 2

Thank you :)