All shampoos have alkaline already in them for cleaning your hair, although a strong amount of alkaline can damage your hair. The water also has alkaline in it already. While the alternative product is more acidic it does not clean as well. Overall Alkaline is best for the cleaning of hair.
Density = mass/volume
Therefore,
Density = 60g/30cm
Answer : 1.12 grams
Yo find the mass of the sample, you take the increased mass and subtract the original mass.
6.130 - 5.010 = 1.12