What do physical changes do? alter the chemical structure of a substance becomes a new chemical substance increase the total mass of a substance affect the size, shape, and phase of a substance

The correct answer is D. Affect the size, shape, and phase of a substance

Explanation:

In chemistry, a physical change occurs when a substance changes its state, and other features such as color or size without changing its structure, composition or properties as it occurs in chemical changes that involve a change in composition or formation of new substances. An example of this is water that changes its state to gas if it reaches its boiling point or to ice if the temperature is reduced. However, this only changes the size, shape, and phase of water without altering its composition. Also, this change is reversible. This implies, physical changes only "affect the size, shape, and phase of a substance".

this is under sat questions? my answer is by walking

answer:

1,800

explanation:

4000 - 3,200 = 1,800