Answer
$10783.7\space J$
Work Step by Step
Here we use the equation $W=\frac{1}{2}Kx^{2}$, where W- Work done by the cord, K-Spring constant, x- stretched distance of the cord.
$W=\frac{1}{2}Kx^{2}$
Let's plug known values into this equation.
$W=\frac{1}{2}\times 235\space N/m\times (9.58\space m)^{2}$
$W=10783.7\space J$
Work done by the cord = 10783.7 J