The latent heat of vaporization of a substance is the amount of energy associated with doing which of the following to 1 kg of the substance? ( need answer )

B) Boiling it at its boiling point

Explanation:

As we know that the heat required to convert the given substance from liquid to vapor at its boiling point is known as latent heat of vaporization

So here we know that

here we know that

so it is known as the heat required to boil the given substance of unit mass at its boiling point

so correct answer will be

B) Boiling it at its boiling point

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.