When the following equation is balanced, the sum of all the coefficients is co + no → co2 + n2.

7

Explanation:

The balanced reaction is as follows:

Coefficient of CO = 2

Coefficient of NO = 2

Coefficient of CO2 = 2

Coefficient of N2 = 1

Sum of all coefficient = 2 + 2+ 2+ 1

                                    = 7

they are non-matter

explanation:

they are non-matter. basically, any type of energy or any abstract concept is an example of something that does not matter. other examples include dreams, magnetism, radio, and hate

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s