Which represents a balanced chemical equation?

co(2) + 2h(2)0 → 2ch(4) + 20(2)
ch(4) + o(2) → co(2) + h(2)o
ch(4) + 20(2) → co(2) + 2h(2)o
co(2) + h(2)o → ch(4) + o(2)

The answer to your question is the third one

Explanation:

Check which reaction is balanced

a)                           CO₂ + 2H₂0 → 2CH₄ + 20₂

                       Reactants                          Products

                             1                   C                    2

                             4                  H                    8

                             4                  O                    4

This reaction is unbalanced because the number of reactants is different from the number of products.                  

b)                              CH₄ + O₂ → CO₂ + H₂O

                     Reactants                          Products

                             1                   C                    1

                             4                  H                    2

                             2                  O                    3

This reaction is unbalanced because the number of reactants is different from the number of products.        

c)                         CH₄ + 20₂ → CO₂ + 2H₂O

                     Reactants                          Products

                             1                   C                    1

                             4                  H                    4

                             4                  O                    4

This reaction is balanced because the number of reactants is equal to the number of products.        

d)                          CO₂ + H₂O → CH₄ + O₂

                     Reactants                          Products

                             1                   C                    1

                             2                  H                    4

                             3                  O                    2

This reaction is unbalanced because the number of reactants is different from the number of products.        

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.

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.