Answer:D
Step-by-step explanation:
It’s D for sure
Answer: 
Step-by-step explanation:
Given
Cost of white-washing =Rs. 4989.60
Rate =20 per meter square
So, inside area of = 
The surface area of dome= 

The volume of air in the dome 

Answer:
The sides are 6, 6 and 9
Step-by-step explanation:
Isosoles triangles have two sides the same length, s
Here the third side is 3 meters longer (s + 3)
therefor the perimeter is
s + s + (s + 3) = 21
Combine like terms
3s + 3 = 21
Subtract 3 from both sides
3s = 18
Divide both sides by 3
s = 6
s + 3 = 9
The sides are 6, 6 and 9