Final answer:
To calculate the volume of a sphere, the formula V(r) = 4/3 π r^3 is used. For a radius of 3 inches, the volume is approximately 113.1 cubic inches, and for a radius of 12 cm, the volume is approximately 7238.2 cubic centimeters, both rounded to the nearest tenth.
Step-by-step explanation:
The volume of a sphere can be calculated using the formula V(r) = \( \frac{4}{3} \pi r^3 \), where V(r) is the volume and r is the radius of the sphere.
Part a:
For a sphere with a radius of 3 inches, the volume is:
V(3) = \( \frac{4}{3} \pi (3)^3 \) = \( \frac{4}{3} \pi \times 27 \) = \( \frac{4}{3} \times 3.1416 \times 27 \) ≈ \( 113.1 \) cubic inches (rounded to the nearest tenth).
Part b:
For a sphere with a radius of 12 cm, the volume is:
V(12) = \( \frac{4}{3} \pi (12)^3 \) = \( \frac{4}{3} \pi \times 1728 \) = \( \frac{4}{3} \times 3.1416 \times 1728 \) ≈ \( 7238.2 \) cubic centimeters (rounded to the nearest tenth).