FREE POINTS! Alright, there are no free points but you do get points if you answer correctly.

One of the skylights on the roof of Bianca’s building is in the shape of the solid below.

A rectangular pyramid has a base of 14 inches by 14 inches and a height of 9 inches. A rectangular prism has a length of 14 inches, width of 14 inches, and height of 2 inches.

What is the total volume of air inside the skylight?

A) 392 inches cubed
B) 588 inches cubed
C) 870 inches cubed
D) 980 inches cubed

B. 588 inches cubed.
Step-by-step explanation:
the pyramid base with 2inch height = 392 - 14 x 14 = 196 = 392-196 = 196
the pyramid with 9 inch height = 588.25 = 14 x 14 = 196 the adjoined upper base.
= 588.25 - 196 = 392.25 + 196 = 588^3 (inches cubed ) we only needed one base structure
We check the slant = (1/2)base = 7 then divide 392.25/7 = 56.0357142857/4
Then divide by 4 = 56.0357142857/4 = 14 and we know the slant is also 14.
We can find the isosceles central height and know it will be the smaller measure as it always is, using 14^2 - 7^2 = a^2
= 196sr - 49sr = 47sr
a^2 = √47 = 6.8556546004
So we know the diagram isn't to scale.
The equation of a rectangle pyramid =
A=lw+√l (w2)
2+√ 2+w
(l2)2+√ h2
The base is l*w*h - l*l = 392-196
or l*w + 4* h*w =196