HELP PLSS GIVING AWAY POINTS A. The atoms in the model would move perpendicular to the direction of the incoming wave.

B. The wavy arrows representing sound waves would go in the opposite direction

C. The atoms in the model would move parallel to the direction of the incoming wave.

D .The wavy arrows representing sound waves would have a smaller wavelength.

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e