document.write( "Question 1044876: Asking this question again as was responded too but no answer was given:\r
\n" ); document.write( "\n" ); document.write( "Need to find the surface area of composite figures and leave answer in terms of pi. The first figure is a cone with a radius of 10mm and a height of 24mm (does not give the slant height) and inside is a hemisphere with a radius of 8mm.
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Algebra.Com's Answer #660313 by KMST(5328)\"\" \"About 
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In a right circular cone, the base radius, \"r\" is perpendicular to the height, \"h\" .
\n" ); document.write( "Radius, height, and slant height form a right triangle,
\n" ); document.write( "and the slant height can be calculated using the Pythagorean theorem as
\n" ); document.write( "\"sqrt%28h%5E2%2Br%5E2%29\" .
\n" ); document.write( "So, when given \"r\" and \"h\" , the lateral surface area of a right circular cone can be calculated as
\n" ); document.write( "\"pi%2Ar%2Asqrt%28h%5E2%2Br%5E2%29\" .
\n" ); document.write( "With \"h=24\" and \"r=10\" ,
\n" ); document.write( "the slant height is \"sqrt%2824%5E2%2B10%5E2%29=26\" ,
\n" ); document.write( "and the lateral surface area is \"pi%2A10%2A26=260pi\" .
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\n" ); document.write( "I assume that your composite figure is a cone with a hemisphere taken out of the base, so that the cross section looks like this:
\n" ); document.write( " , and only a ring is left of the base of the cone,like this: .
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\n" ); document.write( "The surface area of that ring that is left over of the base of the cone
\n" ); document.write( "is the area of a circle of radius \"10\"
\n" ); document.write( "minus the area of a circle of radius \"8\" ;
\n" ); document.write( "\"pi%2A10%5E2-pi%2A8%5E2=100pi-64pi=36pi\" .
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\n" ); document.write( "The surface area of a sphere of radius \"r=8\" is \"4%2Api%2A8%5E2\" ,
\n" ); document.write( "so the surface of a hemisphere of radius \"8\" is
\n" ); document.write( "\"2%2Api%2A8%5E2=2%2Api%2A64=128pi\" ,
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\n" ); document.write( "The surface area of your composite figure is mad of three parts:
\n" ); document.write( "lateral surface area of the cone =\"260pi\" ,
\n" ); document.write( "area of ring on the cone base =\"36pi\" , and
\n" ); document.write( "area of hemisphere =\"128pi\" .
\n" ); document.write( "Total surface area =\"260pi%2B36pi%2B128pi=highlight%28424pi%29\" .
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