Explanation:

- The volume of a sphere is calculated using the formula: \( V = \frac{4}{3} \pi r^3 \).

- For the first ball (radius 2 cm): Volume = \( \frac{4}{3} \pi (2)^3 \).

- For the second ball (radius 4 cm): Volume = \( \frac{4}{3} \pi (4)^3 \).

- For the third ball (radius 6 cm): Volume = \( \frac{4}{3} \pi (6)^3 \).

- Calculate the total initial volume by adding all three volumes.

- Account for the 25% material loss, keeping only 75% of the initial total volume.

- Use the remaining volume to find the radius of the new ball using \( r = \left(\frac{3V}{4\pi}\right)^{\frac{1}{3}} \).

- Solving results in a new radius of 6 cm.

Option 1: 6 cm

- Correct Answer: Option 1: 6 cm.

- .