Answer: Part A the right sentence is: Because the proton is a positive charge and it slows down as it travels, it must be moving from a region of lower potential to a region of higher potential
Part B. aproximatelly 98 times ΔV V
Part C. the initial kinetic energy of the proton is 1.87 10^3 eV
Explanation: Part A. The field stops the proton so the lines of electric fild must be directed in opposite direction of its movement. This means that the proton moves to a higher potential. Part B The kinetic energy of the is transformed in electric potenctial for the proton.
Part C. Energy in J divide the charge of electron gives the energy in eV.
Force on a moving charge is given by formula

here we know that this force will be maximum when velocity is perpendicular to magnetic field

here we know that



now we have


Answer: E) A) salt water.
Explanation:
E) In equilibrium, pressure exerts equally in all directions, so for a given depth, the pressure is the same for all points located at the same depth, and it can be written as follows:
p = p₀ + ρ.g.h, where p₀ = atmospheric pressure, ρ=fluid density, h=depth from the surface.
A) The buoyant force, as discovered by Archimedes, is an upward force, that opposes to the weight of an object (as it is always downward), and is equal to the weight of the volume of the liquid that the object removes, which means that is proportional to the density of the liquid.
As salt water is denser than fresh water, the buoyant force exerted by the salt water is always greater than the one produced by the fresh water, so objects will float more easily in salt water than in fresh water.
In the limit, it is possible that one object float in salt water and sink in fresh water.