1st : Find the volume of the rectangular block:
12 × 10 × 20 = 2400 cm^3.
2nd : Find the volume of a cylinder

Where r is radius & h is height.
so:

= 76.02654222 cm^3
Lastly, divide the volume of the rectangular block by the volume of the cylinder
2400 ÷ 76.026 = 31.5679226
You can't round it up so the answer is F) 31