Definition of negative exponent:
Following the definition, we have:
Answer: -9
I think it is this answer
The surface area of a cone is : pi•r•slant height + pi•r^2
If d=28 then r=14
Use the pythagorean theorem to find the slant height c^2 = 14^2 + 22^2
C^2 = 680
C = 26.08 (rounded)
Pi•14•26.08 + 196pi = 1,762.67 squared cm
Use the proportion 8/64 = 12/y. Cross multiply to get 8y = 768. Divide both sides by 8 to get y=96