Question 1090452
If you look at the xz plane, the triangle looks like this,
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*[illustration cone.png].
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So rotating the triangle will lead to a cone with radius of 1 and height of 1.
{{{V=(pi/3)r^2*h}}}
Substituting,
{{{V=(pi/3)1^2*1}}}
{{{V=pi/3}}}