if your not able to reverse it that means it is a chemical change and with toast you cant reverse the color if the color has changed that most likely means it is a chemical change.
Gravity is often assumed to be the same everywhere on Earth, but it varies because the planet is not perfectly spherical or uniformly dense. In addition, gravity is weaker at the equator due to centrifugal forces produced by the planet's rotation
The correct answer to the question is : C) Speed is the distance an object travels within a specific unit of time, whereas acceleration is the rate at which the speed or direction of an object is changing.
EXPLANATION :
Before going to answer this question, first we have to understand speed and acceleration.
The speed of a body is defined as the rate of change of distance or the distance covered by the body per unit time. Speed is scalar quantity. Hence, it needs only magnitude for its complete specification.
The acceleration produced by a body is defined as the rate of change of velocity. We know that velocity is the speed in a particular direction. Hence, the acceleration is not only produced due to the change in magnitude of velocity as well as due to the change in direction. Hence, acceleration is a vector quantity which needs magnitude as well as direction for its complete specification.
Hence, the best difference between speed and acceleration is the third statement.
