Question

The answer please anyone???

Answer 1

The equation for the surface area of a cone is:
`SA = \pi r^(2) + \pi rl`
SA = surface area
r = radius
l = slant height

From the picture, you can see that the radius of the base of the cone, r=3mm. The slant height of the cone (length from base to the top point of the cone along the side of the code), l=12mm.

Plug these numbers into the equation for the surface area of a cone:

`SA = \pi r^(2) + \pi rl\\ SA = \pi (3 \: mm)^(2) + \pi (3 \: mm)(12 \: mm)\\ SA = \pi ((3 \: mm)^(2) + (3 \: mm)(12 \: mm))\\ SA = \pi (9 \: mm^(2) + 36 \: mm^(2))\\ SA = 45\pi \:mm^(2)`
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Answer: C) 45π
`mm^(2)`