Question 214831
volume of a cylinder is {{{pi*r^2*h}}}
each of these tunnels is one half of a cylinder.
l = 50000 meters
r = 4 meters.
volume of each tunnel is {{{(1/2)*pi*4^2*50000}}} = 1,256,637.061 cubic meters.
3 * that = 3,769,911.184 cubic meters.
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that's how much dirt had to be removed.
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