A 025 kg mass on a spring has a displacement xt 02 cos12 t

Question

Compute all parts of given problem:

Problem: A 0.25 kg mass on a spring has a displacement x(t) = 0.2 cos(1.2 t - 0.15?).

Part A: What is the period of this oscillation?

Part B: What is the spring stiffness?

Part C: Determine the initial velocity of the mass.

Part D: What is the total energy of the oscillator?

Part E: Find the maximum speed of the mass.

Part F: At what times did the position equal -0.15m?

Part G: At what times did the kinetic energy equal 0.3 Kmax?

Please show me step by step or type in formulas used. I am so lost!!