Answer:
210*pi
Step-by-step explanation:
Surface area=2*pi*r*(r+h)
=2*pi*5*(21)=210*pi
<span>An obtuse triangle will have one and only one obtuse angle. </span>
<span>The other two angles are acute angles.</span>
<span>The sum of the two angles other than the obtuse angle is less than 90º.<span /></span>
<span><span>The side opposite to the obtuse angle is the longest side of the triangle.</span></span>
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</span><span>The points of concurrency, the Circumcenter and the Orthocenter lie outside of an obtuse triangle, while Centroid and Incenter lie inside the triangle.
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