A solid cubical block of fine wood costs Rs 256 at Rs 500 per m

Cost of wood = Rs $500 / \mathrm{m}^{3}$

Cost of the given block $=$ Rs 256

$\therefore$ Volume of the given block $=\mathrm{a}^{3}=\frac{256}{500}=0.512 \mathrm{~m}^{3}=512000 \mathrm{~cm}^{3}$

Also, length of its edge $=\mathrm{a}=\sqrt[3]{0.512}=0.8 \mathrm{~m}=80 \mathrm{~cm}$