<h3>
Answer: approximately 1,500,000 cubic feet</h3>
This is the same as 1.5 million cubic feet
======================================================
Work Shown:
area of rectangle = length*width
area of rectangle = 40*20
area of rectangle = 800 square feet
area of semicircle = 0.5*(area of circle)
area of semicircle = 0.5*pi*r^2
area of semicircle = 0.5*pi*20^2
area of semicircle = 200*pi .... exact area
total area = (rectangle area) + (semicircle area)
total area = 800 + 200pi
total area = 1428.31853 approximately
-----------------
Multiply this with the length of the tunnel to get the volume
volume of tunnel = (cross sectional area)*(length of tunnel)
volume of tunnel = 1428.31853*1050
volume of tunnel = 1,499,734.4565
Rounding to the nearest 100,000 cubic feet, we get roughly 1,500,000 cubic feet as the approximate volume.
