Question 1157788
Do you mean the height of the cone when you say length? The surface area S can be found by the following formula, {{{S=pi*r*sqrt(h^2+r^2)}}}, where r is the radius and h is the height. Plugging in 3 for r and 4 for h, we get {{{S=pi*4*sqrt(4^2+3^2)}}}, which is equal to {{{pi*4*sqrt(25)=pi*4*5=highlight(20*pi)}}}.