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प्रश्न
The total surface area of a hemisphere of radius r is
विकल्प
- \[\pi r^2\]
2 \[\pi r^2\]
3 \[\pi r^2\]
4 \[\pi r^2\]
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उत्तर
The curved surface area of a hemisphere of radius r is
2 \[\pi r^2\] So, the total surface area of a hemisphere will be the sum of the curved surface area and the area of the base.
Total surface area of a hemisphere of radius r =
2 \[\pi r^2\] + \[\pi r^2\]
=3 \[\pi r^2\]
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