Scaling the Moon's radius using Earth's model ratio

Steps:

• Calculate the radius ratio of Moon to Earth: (1.7 × 10^6 m) / (6.4 × 10^6 m) ≈ 0.266.
• Apply ratio to model Earth radius: 0.1 m × 0.266 ≈ 0.0266 m (2.66 cm).
• Estimate radii of options: basketball ≈12 cm, cherry ≈1 cm, golf ball ≈2.1 cm, tennis ball ≈3.3 cm.
• Identify closest match to 2.66 cm as tennis ball.

Why D is correct:

• Scale factor formula (model size = actual ratio × model reference) yields ≈2.7 cm radius, aligning with tennis ball dimensions.

Why the others are wrong:

• A. Basketball's 12 cm radius exceeds scaled size by factor of 4.5.
• B. Cherry's 1 cm radius is 2.7 times smaller than required.
• C. Golf ball's 2.1 cm radius underestimates by 20%.

Final answer: D