Answer:

Step-by-step explanation:
Since we see that 3/7 is multiplied by itself three times, we can use exponents as a shorter way to write this. The expontent tells us how many times the base number, 3/7, is multiplied by itself.
= 
We then multiply by -1 to (3/7)^3 to get the exact answer.

Given:
Volume of the cone = π r² h/3
radius of the cone is half the radius of the cylinder ⇒ r/2
height of the cone is equal to the radius of the cylinder. ⇒ r
V = 3.14 * (r/2)² * r/3
V = 3.14 * r²/4 * r/3
V = 3.14r³ / 12