Main principle of answer - Volume of old and new solids will remain EQUAL.
1. Volume of Hemisphere = Volumer of Right Circular Cylinder
2. Volume of Hemi = 2*pi*radius square
3. Volume of RCC = pi*radius square*height
Put in the values and find the answer! The external diameter should be considered the diameter of the whole bowl while the internal diameter is the diameter of the bowl excluding the boundary. You have to use external diameter in this question.
may it be easy