1. Calculate the surface area of a sphere with radius 6 cm. The formula for the surface area of a sphere is $$4\pi r^2$$. Substitute $r = 6$ cm: $$4 \times \frac{22}{7} \times 6^2$$ $$= 4 \times \frac{22}{7} \times 36$$ $$= \frac{4 \times 22 \times 36}{7}$$ $$= \frac{3168}{7}$$ $$\approx 452.57 \text{ cm}^2$$ 2. Calculate the curved surface area of a hemispherical bowl with radius 4.5 cm. The curved surface area of a hemisphere is half the surface area of a sphere, which is: $$2\pi r^2$$. Substitute $r = 4.5$ cm: $$2 \times \frac{22}{7} \times 4.5^2$$ $$= 2 \times \frac{22}{7} \times 20.25$$ $$= \frac{2 \times 22 \times 20.25}{7}$$ $$= \frac{891}{7}$$ $$= 127.29 \text{ cm}^2$$ 3. Find the volume of a sphere with diameter 8 m. First, find the radius: $$r = \frac{8}{2} = 4$$ m. The volume formula for a sphere is: $$\frac{4}{3}\pi r^3$$. Substitute $r = 4$ m: $$\frac{4}{3} \times \frac{22}{7} \times 4^3$$ $$= \frac{4}{3} \times \frac{22}{7} \times 64$$ $$= \frac{4 \times 22 \times 64}{3 \times 7}$$ $$= \frac{5632}{21}$$ $$\approx 268.19 \text{ m}^3$$