Determine the total surface area of a hemisphere closed at bottom. Radius of the hemisphere is $\sqrt{\frac{25}{\pi}}$ unit.

75 unit2 70 unit2 60 unit2 50 unit2

75 unit2

We know that, TSA of hemisphere = 3πr2  We have, Radius of the hemisphere = $\sqrt{\frac{25}{\pi}}$ unit. According to the question, TSA = 3π [$\sqrt{\frac{25}{\pi}}$]2  = TSA = 3π × \(\frac{25}{ π }\) = 3 × 25 = 75 unit2