Given:
The radius of the base of the given cone = 5 cm
The slant height of the cone = 19 cm
To find the surface area of the given cone.
Formula
The surface area pf the given cone is,
where, r be the radius and
l be the slant height.
Now,
Taking, r = 5, l = 19 and π = 3.14 we get,
sq cm
or, sq cm
or, sq cm
Rounding off to the nearest square centimeter, we get;
Hence,
The surface area of the cone is 377 sq cm.
270 I think but I’m not 100% sure
Central angle of a regular polygon:
Ф = 360° : n.
If n=12: Ф = 360° : 12 = 30°
At the angle of rotation Ф = 30° the image of the polygon will coincide with the preimage.
What are the choices, or do you have to give the answer?
