20.18 using the following data, calculate the work done by stretching a spring that has a spring constant of k 300 n/m tox-0.35 m. to do this, first fit the data with a polynomial and then integrate the polynomial numerically to compute the work: f, 103. n , m 0.01 0.05 0 0.028 0.10 0.046 0.15 f, 103.n 0.063 0.082 0.1 0.13 0.35 x, m 0.20 0.25 0.30