A dome of a building is in the form of a hemisphere. From inside, it was white-washed

A dome of a building is in the form of a hemisphere. From inside, it was white-washed at the cost of ₹ 498.96. If the cost of white-washing is ₹ 2.00 per sq m, then find the
(i) inside radius of the dome.
(ii) volume of the air inside the dome.
[take, π = 22/7]

Given, cost of white-washing =₹ 498.96
and cost of white-washing per square metre = ₹ 2.00 per sq m
Curved surface area of inside the dome
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(i)Let r be the radius of the dome.
Curved surface area of inside the dome
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(ii)Volume of the air inside the dome
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