Question

Find the volume and surface area of the composite figure. Give four answer in terms of π.

Answer 1

The answer to your question is, V = 53.3π
`in^(3)`; S = 60π
`in^(2)`

Explanation:

Diameter = 4 in.

Radius of cylinder and hemi - sphere = 4/2 = 2 in .

Height or cylinder = 12 in.

If the problem is written out like this then...

Surface Area of figure = 2πr² + (2πrh + πr²) = 3πr² + 2πrh = πr(3r + 2h) = 2π(3*2 + 2*12) = 2π(6 + 24) = 2 * π * 30 = 60π in² . < Important

and if it is like that it will then be concluded like the following:

Volume of figure = (2/3)πr³ + (πr²h) = πr²[(2r/3) + h] = 4π[(4/3) + 12)] = 4π * (40/3) = (160π/3) = 53.3π in³ . < Answer

Thus, the answer to your question is, V = 53.3π
`in^(3)`; S = 60π
`in^(2)`.