Answer:
The period of the resulting oscillatory motion is 0.20 s.
Step-by-step explanation:
Given that,
Spring constant

We need to calculate the time period
The object is at rest and has no elastic potential but it does has gravitational potential.
If the object falls then the the gravitational potential change in to the elastic potential.
So,


Where,h = distance
k = spring constant
Put the value into the formula


Using formula of time period

Put the value into the formula


Hence, The period of the resulting oscillatory motion is 0.20 s.