Radius of conical depression, r = 0.5 cm.

(Depth) height, h = 1.4 cm.

Volume of 1 depression which is conical,

Volume of such 4 depressions

= 4 x \(\frac{11}{30}cm^3\)

= \(\frac{44}{30}\)cm^{3}

∴ Total volume of wooden pen-stand,

= (15 x 10 x 3.5) - \(\frac{44}{30}\)

= 525 – 1.47

= 523.53 cm^{3}