A cathode ray tube is made of glass with a small amount of some kind of gas in it. It has metal electrodes at each end to pick up an electric current. The electrodes are named "positive” and "negative,” which were words used by Benjamin Franklin in the 1700s to describe electricity. A bright ray forms in the gas when an electric current is applied to metal electrodes. In the 1800s, an important scientist suspected that the negatively charged particles in a cathode ray were present in all atoms.

What procedure would allow that scientist to investigate this idea?

a.)observing if the cathode ray forms when the electric current is off
b.)making cathode ray tubes out of different materials to see if the ray is the same
c.)using different magnets to see if the cathode ray responds in the same way to each
d.)changing the strength of the electric current and observe how the ray forms and changes

a. are

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.

distance = 150m

displ = root (50 ^2 + 100^2)

root(2500+10000)

root 125000