The amount of force required to stretch or compress the spring is known as the spring force. Its unit is Newton(N). Force is needed to stretch spring is 10.2 N.
<h3>What is spring force?</h3>
The force required to extend or compress a spring by some distance scales linearly with respect to that distance is known as the spring force. Its formula is
F = kx
The given data in the problem is;
F is the spring force =?
K is the spring constant= 8.5 N/m
x is the length by which spring got stretched = 1.2m

Hence the force is needed to stretch the spring is 10.2 N.
To learn more about the spring force refer to the link;
brainly.com/question/4291098
<h2>
Option C is the correct answer.</h2>
Explanation:
Specific gravity of fluid = 0.750
Density of fluid = Specific gravity of fluid x Density of water
Density of fluid = 0.750 x 1000
Density of fluid = 750 kg/m³
Mass of fluid = 22.5 kg
We have
Mass = Volume x Density
22.5 = Volume x 750
Volume = 0.03 m³ = 30 L
Option C is the correct answer.
The third choice is correct
A, electrons are negatively charged and do orbit around the nucleons
I think that’s the correct answer