ok first i am going to convert all the units given in tat question to SI units (i was taught in SI units)

mass of the collar, m = 0.17 kg (1 oz = 0.0283495231 kg)

spring constant, k =875.83 N/m (1 lb/in = 175.166 N/m)

distance spring compressed, x = 0.0381 m (1 inch = 0.0254 m)

Now total elastic potential energy,EPE stored in the spring before release is given by the formula,

The collar is then released. At point B, the collar has already traveled 10 inches (0.254 m) vertically upwards.

Hence gravitational potential energy,GPE gained by the collar is:

using principle of conservation of energy the total energy of the system is conserved:

Initial energy = final energy

EPE = Kinetic energy + GPE

0.635681793J = KE + 0.4235958J

KE = 0.21085993 J

from the formula of kinetic energy, KE:

well as for the force part take note that:

elastic potential energy, EPE =