Please answer 14 a, b,c,d and 19. Thank you!

14. A block of mass 20 kg on a horizontal surface where uk = 0.4 is pushed against an initially relaxed spring that has a force constant k = 100 N/m, compressing it 1.50 meters. It is then released, what is the maximum velocity of the mass? Hint the maximum velocity occurs before the relaxed spring equilibrium point. a. Find the position where the acceleration is zero-where the force of the spring = the force of friction b. How much potential energy does the spring have at that point? c. How much work does friction do to get to that point? d. What is the kinetic energy of the block at that point and what is its velocity?19. Two freight cars are moving in the same direction, on a level track with negligible friction. One freight car has a mass of 2500 kg and has a velocity of 22.5 m/s the other has a mass of 2200 kg and a velocity of 2.7 m/s After the collision, both cars are coupled and roll together with what speed? How much kinetic energy is lost in this collision