Rust forming on iron is an indication of which of the following?

a. atoms are being destroyed
b. a gas is forming
c. a chemical change is occurring
d. matter is being created

C. a chemical change is occurring

Explanation:

Chemical change is a change in which rearrangement of atoms take place and thus formation of new substances take place.

Corrosion of iron is called as rusting. Rusting is oxidation of iron in the presence of oxygen and water and leads to formation of hydrated ferric oxide .

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.