Question

Find the volume and surface area of the composite figure. Give four answer in terms of π. HELP NEEDED NOW!!! THE RED IS THE ONE I GOT WRONG!!

Answer 1

Answer:

Divide the figure above into a cylinder and a dome

+) the volume of the dome is

$v1 = \frac{1}{12} \pi6 {}^{3} = 18\pi$

the surface area is

$s1 = \pi3 {}^{2} = 9\pi$

+) the volume of the cylinder is

$v2 = \pi.3 {}^{2} .13 = 117\pi$

the surface area is

$s2 = 2\pi.3.13 + 2\pi.3 {}^{2} = 96\pi$

so the volume of this figure is

$v = v1 + v2 = 18\pi + 117\pi = 135\pi$

the surface area of this figure is

$s = 9\pi + 96\pi = 105\pi$