Answer:The amount if mass of all substances before or after a chemical change are equal
Explanation:
Heat normally travels from areas of higher heat to areas of lower heat. For example, if you were to be in a classroom and all the windows and doors were closed, and then you opened a door, then the reason why the room becomes cooler is not because cold air comes inside the room. However, it is because when you open the door, the heat from the classroom you're in escapes the room. This is why it feels cooler when you open a door, or even a window. Heat is traveling from areas of higher heat to areas of lower heat.
Answer:
a = 3.125 [m/s^2]
Explanation:
In order to solve this problem, we must use the following equation of kinematics. But first, we have to convert the speed of 90 [km/h] to meters per second.


where:
Vf = final velocity = 25 [m/s]
Vi = initial velocity = 0
a = acceleration [m/s^2]
t = time = 8 [s]
The initial speed is zero as the bus starts to koverse from rest. The positive sign of the equation means that the bus increases its speed.
25 = 0 + a*8
a = 3.125 [m/s^2]
For this case we have that by definition, the kinetic energy is given by the following formula:

Where:
m: It is the mass
v: It is the velocity
According to the data we have to:

Substituting the values we have:

finally, the kinetic energy is 
Answer:
Option A
Everywhere particles dont stay in one place they move elsewhere