The correct answer is C) A substance changes color when heated, but changes back when cooled. Hope this helps.
Answer: oh my gosh, yes I relate with this so much. Don’t worry, you are not alone and you will get through this.
Explanation:
The objects may exchange heat between each other if they are in contact with each other.
The two objects will allow flow of heat between them if they have a difference in temperature from each other.
The heat will flow from higher temperature object to lower temperature object. The will reach a final temperature (common to each other) and then there will be no heat transfer between each other.
Answer:
Kinetic energy is directly proportional to mass
Explanation:
Kinetic energy is directly proportional to the mass of an object and also directly proportional to the square of the velocity of that object:

Notice that if we keep velocity constant and only increase the mass of a object, the kinetic energy of that object would increase, as we've already emphasized the direct relationship between the kinetic energy term and the mass term.
Let's take a simple example: assume that object 1 and object 2 are both moving at the same velocity but object 1 has a much lower mass than object 2. According to the equation, object 1 has lower kinetic energy. This object can then transform all of its kinetic energy into some other form, say, heat the ground. The heat transferred will be significantly lower than by the object 2 moving at the same velocity but having a much greater mass.