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The total surface area of a solid hemisphere of radius r equals:
Answer & Solution
Correct answer: C.
1. The curved surface of a hemisphere equals half the sphere's surface, 2 π r².
2. The flat circular base of the hemisphere has area π r².
3. Total = 2 π r² + π r² = 3 π r².
4. So total surface area of a solid hemisphere = 3 π r².
5. 2 π r² alone misses the circular base; 4 π r² is the full sphere.
_Source: SCERT Kerala Std X Mathematics Part-2, Chapter 8-9 (pp 200-219, 2019 ed.)._
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