Answers
n1.) Using PEs=1/2kx2  you know “x” but not “k”
nYou can find “k” using Fs=kx
nWith Fs equal to the weight of the hanging mass
nSo… Fs=Fg=mg=2kgx9.81m/s2
nFs=19.62N=kx=k x 0.25m
nk=78.48N/m
nMore…