The blocks are forced together, compressing a spring between them by a distance x; (the force constant of the spring is k) then the system is released from rest on a level, frictionless surface. The spring, which has negligible mass, is not fastened to either block and drops to the surface after it has expanded. What is the speed that block A acquired, vA

   v =    x

Explanation:

For this exercise let's use the important topic of conservation of energy

starting point. Spring compression point

          Em₀ = K_e = ½ k x²

final point. When the spring is not compressed

          Em_f = K = ½ m v²

as they indicate that there is no friction, the energy is conserved

          Em₀ = Em_f

          ½ k x² = ½ m v²

          v =    x

it breaks and dirupture other materials and other sencews from the bottom

distance = 150m

displ = root (50 ^2 + 100^2)

root(2500+10000)

root 125000