Answer:

Explanation:
Hello,
In this case, since a change in science is widely known to be considered as a subtraction between the the final and initial values of two measured variables and is represented via Δ, here the final density is 5.43 g/mL and the initial one was 3.21 g/mL, therefore, the change in density is:

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Mouthwash:
solvent - water
solute - alcohols
vinegar:
solvent - water
solute - acetic acid
bleach:
solvent - water
solute - sodium hypochlorite
hope this helps!!