A standard refill tube is a cylinder of internal radius about 0.1 cm and ink length 10 cm. The ink volume is πr²h ≈ 3.14 × (0.1)² × 10 ≈ 0.314 cm³ (or ~0.3 mL).

Ganita Manjari Part 2 Class 9 Maths Chapter 14 Math of Space: Surface Area and Volume Solutions
Class 9 Maths Ganita Manjari Part 2 Chapter 14 Question Answer