The height is 22 inches? It says it in the question
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 

Think of the "of" as a multiplication sign:
(.15)(12)= 1.8 meters
There you go! hope this helps with this problem and future ones.
Well if the flat fee is $4 and you pay $2 per mile and she spent a total of $32, the answer would have to be 14 miles