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:
Answer:
A 5
Explanation:
The wave with the least amount of wavelength will have the greatest amount of energy.
Wavelength and energy shares an inverse relationship;
E = h f = 
From this equation, we see that the higher the energy of a wave, the lesser its wavelength.
- Choice A from the options has the least wavelength.
- Wavelength is the distance between two successive crests of a wave.
This is why we see that in the electromagnetic spectrum, radio waves have the least energy because they have the longest wavelength.
It’s because flourecent lights operate at higher temperatures than incadecent lights.
Answer: The initial force is reduced a factor 1/4 when the separation between charge is doubled
Explanation: As it well known the electric force between two charges is given by:
Finitial=k*q1*q2/d^2 where d is the distance between charges and k is a constant
if the distance is doubled this means 2*dinitial thus the new force is equal to F initial* 1/4