Physical change .. you cannot undo chemical ... physical is like bending , shattering a mirror , denting something ..
chemical would be rust or something .
Answer:
C. Shape
Explanation:
Did the quiz! & galaxies are classified by shapes called "elliptical, spirial, & irregular"
Good luck :)
the answer is dure light I'm not sure of this answer ,but it might be to go with .
Answer: After three half-lives 1/8 (12.5%) of the original sample remains
Gravity, its what holds the whole universe together