Missing question: "What is the spring's constant?"
Solution:
The object of mass m=6.89 kg exerts a force on the spring equal to its weight:

When the object is attached to the spring, the displacement of the spring with respect to its equilibrium position is

And by using Hook's law, we can find the constant of the spring:
The sensation of a frequency is commonly referred to as the pitch of a sound. A high pitch sound corresponds to a high frequency sound wave and a low pitch sound corresponds to a low frequency sound wave. ... That is, two sound waves sound good when played together if one sound has twice the frequency of the other.
Answer:
The possible thickness of the soap bubble = 
Explanation:
<u>Given:</u>
- Refractive index of the soap bubble,

- Wavelength of the light taken,

Let the thickness of the soap bubble be
.
It is given that the soap bubble appears very bright, it means, there is a constructive interference takes place.
For the constructive interference of light through a thin film ( soap bubble), the condition of constructive interference is given as:

where
is the order of constructive interference.
Since the soap bubble is appearing very bright, the order should be 0, as
order interference has maximum intensity.
Thus,

It is the possible thickness of the soap bubble.