Answer:
Support
Posture
Protection
Explanation:
Support – the skeleton keeps the body upright and provides a framework for muscle and tissue attachment.
Posture – the skeleton gives the correct shape to our body.
Protection – the bones of the skeleton protect the internal organs and reduce the risk of injury on impact.
Answer:
we go up the ramp there is a point where the beam is reflected inside the block, we carefully step back to the point where the beam is horizontal, we measure this angle which is our critical angle.
Explanation:
To design the experiment of measuring the critical angle, we describe the phenomenon, when the light passes from a medium with a higher refractive index to one with a lower index, it separates from the normal one and the Critical Angle is defined as the Angle for which the refraction occurs at 90º
n₂ sin θ₂ = n₁ sin 90
n₁ / n₂ = sin θ₂
As we can see, we have to measure the angle with which the laser touches the exit surface of the glass block.
Design of the experiment:
We place the glass block on the ramp and at the top we hit the conveyor for half the angle, we climb the block on the ramp and see that the angle of incidence of lightning on the exit face changes, part of the beam comes out of the glass , we see it by dispersion in the particles of dirty in the air; Maybe the conveyor or the laser should be moved slightly so that the beam touches the point of origin on the conveyor.
When we go up the ramp there is a point where the beam is reflected inside the block, we carefully step back to the point where the beam is horizontal, we measure this angle which is our critical angle.
Answer:
A) F_g = 4.05 10⁻⁴⁷ N, B) F_e = 9.2 10⁻⁸N, C)
= 2.3 10³⁹
Explanation:
A) It is asked to find the force of attraction due to the masses of the particles
Let's use the law of universal attraction
F = 
let's calculate
F = 
F_g = 4.05 10⁻⁴⁷ N
B) in this part it is asked to calculate the electric force
Let's use Coulomb's law
F = 
let's calculate
F = 
F_e = 9.2 10⁻⁸N
C) It is asked to find the relationship between these forces

= 2.3 10³⁹
therefore the electric force is much greater than the gravitational force
A surface wave is a wave that travels along the surface of a medium. The medium is the matter through which the wave travels. Ocean waves are the best-known examples of surface waves. They travel on the surface of the water between the ocean and the air. (According to ck12.org)
So your answer would be A!