Physical change is the change we can see with our eyes. Chemical change is the change that we cannot see. Examples: physical change: The Polar ice caps are melting, and we can see that as it happens. Chemical change: The cooking of an egg or some combustion, like a fire. We can't see the chemicals coming from the fire, but there are chemicals coming from what is being burned and is being released into the air that we cannot see.
I am very sure that the answer is C. Hope it’s right :)
Answer:
I'm so sorry if this is wrong but I think its B
Answer: 
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
Precipitation is a type of displacement reaction in which one the products is formed in the solid state.

Increase..................