Answer:
200π
Step-by-step explanation:
Surface area of a cone = πr(r+l)
r is the radius
l is the slant height
Volume of the cone = 1/3πr²h
320π = 1/3πr²h
320 = 1/3r²(15)
320 = 5r²
r² = 320/5
r² = 64
r = 8
l² = 15² + 8²
l² = 225 + 64
l² = 289
l = 17
Get the surface area;
S = πr(r+l)
S = π8(8+17)
S = π*8*25
S = 200π
Hence the surface area of the cone is 200π
