Question

which two facts are about physical changes? it is sometimes possible to change the substance back. the change results in a new substance. the change cannot be reversed. the substance changes size or shape but remains the same substance.

Explanation:

Physical changes do not result in new substances. They can often be reversed and involve changes in size, shape etc. of the same substance.

Answer:

It is sometimes possible to change the substance back.
The substance changes size or shape but remains the same substance.