Hemisphere volume = $\frac{1}{2} \times \frac{4}{3}\pi(5)^3 = \frac{250\pi}{3}$ cm³

Hemisphere volume = $\frac{4}{3}\pi(5)^3 = \frac{500\pi}{3}$ cm³

Hemisphere volume is $\frac{1}{3}$ of full sphere

Hemisphere volume = $\frac{1}{2} \times \frac{2}{3}\pi(5)^3$ cm³