document.write( "Question 287853: The dimensions of a cylinder, its radius and height are each doubled. What is true about its resulting surface area?\r
\n" ); document.write( "\n" ); document.write( "a) The resulting volume is double the original surface area.
\n" ); document.write( "b) The resulting volume is triple the original surface area.
\n" ); document.write( "c) The resulting volume is 4 times the original surface area.
\n" ); document.write( "d) The resulting volume is 6 times the original surface area.
\n" ); document.write( "e) The resulting volume is 8 times the original surface area. \n" ); document.write( "
Algebra.Com's Answer #208587 by dabanfield(803)\"\" \"About 
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Let h be the original height and r the original radius. The the surface area (two ends and side) is:\r
\n" ); document.write( "\n" ); document.write( "2*(pi*r^2) + (2*r*pi)*h (note that 2*r*pi is the circumference of the cylinder).\r
\n" ); document.write( "\n" ); document.write( "If we double the height and the radius the surface area becomes:\r
\n" ); document.write( "\n" ); document.write( "2*(pi*(2*r)^2) + (2*(2*r)*pi)*h =\r
\n" ); document.write( "\n" ); document.write( "2*4*r^2*pi + 2*2*r*pi*h =
\n" ); document.write( "4*2*(pi*r^2) + 2*(2*r*pi)*h\r
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\n" ); document.write( "\n" ); document.write( "The original volume is (pi*r^2)*h.
\n" ); document.write( "The new volume is (pi*(2r)^2*(2*h)=
\n" ); document.write( "pi*4*r^2*2*h = 8*((pi*r^2)*h)\r
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