120. A rubber cord 10 m long is suspended vertically. How much does it stretch under its own weight (Density of rubber is 1500

A rubber cord 10 m long is suspended vertically. How much does it stretch under its own weight (Density of rubber is 1500 kg/m³, Y = 5×10⁸ N/m², g = 10 m/s²)

(a)   15×10^­–4 m                             (b)   7.5×10^­–4 m                           

(c)   12×10^­–4 m                             (d)   25×10^­–4 m

Answer-a