



 
Hi Nicholas, The surface area of a sphere of radius r is 4 π r^{2}. Half of this is 2 π r^{2}. If this is what is meant by the surface area of a hemisphere then 2 π r^{2} = 1062. Solve for r. If you have a hemispherical object then it has a base which is a circle of radius r. The area of a circle of radius r is π r^{2} and thus if the hemisphere is meant to include the base then the surface area is 2 π r^{2} + π r^{2} = 3 π r^{2}. Hence in this case 3 π r^{2} = 1062. Solve for r. Penny  


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