A mass of 0.60 kg is suspended from the lower end of a light spring of stiffness 150 N m-1. When the mass is displaced vertically and released, it undergoes vertical oscillations of small amplitude. What is the frequency of the oscillations?
0.010 Hz0.010\text{ Hz}0.010 Hz
0.40 Hz0.40\text{ Hz}0.40 Hz
2.5 Hz2.5\text{ Hz}2.5 Hz
99 Hz99\text{ Hz}99 Hz