Question 1: Calculate the surface area of a sphere with a radius of 5 cm. Use π ≈ 3.14.

Answer: 314.00

Question 2: Find the volume of a sphere with a diameter of 12 cm. Use π ≈ 3.14. Show your working.

Answer: 904.78

Question 3: A spherical ball has a surface area of 618.8 cm². Calculate its radius (π ≈ 3.14).

Answer: 5 cm

Question 4: Plot the graph of y = 4/3 π r³, where r ranges from 0 to 10 cm.

Answer: Students to plot on grid

Question 5: Construct a sphere with radius 6 cm on the grid. Label the radius and diameter.

Answer: Constructed circle with radius 6 cm; diameter 12 cm

Question 6: A spherical container has a volume of 288 π cm³. Find its radius in cm, using π ≈ 3.14.

Answer: 6 cm

Question 7: A spherical globe has a radius of 15 cm. Calculate its surface area and volume. Use π ≈ 3.14.

Answer: {"volume":"14137.20","surfaceArea":"1413.00"}

Question 8: A basketball is made with a diameter of 24 inches. Estimate its surface area in square inches.

Answer: 1130.97

Question 9: A spherical water tank has a radius of 10 meters. How much water in cubic meters can it hold? Use π ≈ 3.14.

Answer: 4186.67

Question 10: Common mistake: A student calculates the surface area of a sphere with radius 7 cm using the formula 4πr² but forgets to multiply by π. What is the incorrect answer? (Use π ≈ 3.14)

Answer: 615.8

Question 11: Error analysis: The same student then divides this incorrect surface area by 2. What is the resulting value? Is this value meaningful? Explain briefly.

Answer: 307.9; No, division by 2 doesn't relate to sphere properties.