I need an answer in 10-15 minutes.

a) (8 marks) A 2kg mass is connected to a spring and placed on a frictionless surface, with one end of the spring fixed. Above it, a 5 kg mass is suspended from a string of length 20cm. Both masses are displaced horizontally from their respective equilibrium positions, released from rest and allowed to oscillate freely, and it is noticed that the two systems oscillate in phase. 20 cm 5 kg 2 kg 1) (3 marks) Calculate the value of the spring constant. i) (3 marks) The pendulum reaches a maximum speed of 0.35 m/s. What is the maximum height that the pendulum reaches relative to its rest position? iil) (2 marks) The mass on the spring reaches a maximum speed of 0.7m/s. What is the maximum amplitude of the displacement of the mass on the spring? b) (8 marks) The spring is replaced with one that has a different spring constant, while both masses are kept the same as in part (a). The two systems are now displaced by 5 cm from their respective equilibrium positions and released simultaneously, and it is now observed that the mass-spring system completes 5 full oscillations in the time it takes for the pendulum to complete a single oscillation