The right answer is B. hope this helps you :)
Medicine to a patient. That should be calculated based on weight, strength/dosage and possibly other factors
Answer
4.8 N
If the box is moving with a constant velocity, then we can say that the system is in equilibrium. This is because if the external force (F->) was greater than other forces the box would be accelerating. This tells us that this force (F->) is just enough to overcome friction and so it must be equal to 4.8 N.
The normal force has no effect to the horizontal velocities or forces. It is equal to -Weight. That is -74 N. The negative sign shows that the force is in opposite direction.
Here light ray strikes to interface at an angle of 45 degree and then refracts into other medium such that it will bend towards boundary.
So here the angle of incidence will be less than the angle of refraction as light moves towards the boundary after refraction which mean it will bend away from the normal
here it can be said that medium 2 will be rarer then medium 1
So here the possible options are
1. Water
Air
2. Diamond
Air
So in above two options medium 1 is denser and medium 2 is rarer