Some long circular cylindrical small chocolates were made by a cylindrical chocolate having base radius 6 cm and height 6cm. The radius of base of each small chocolate is 2 cm and height is 2 cm. If the small chocolates are placed in 9 × 3 configuration in a rectangular box and the height of the box is 2 cm, Find the percentage of free space inside the box based on volume? (use π = 3.14)