What is the mass (in amu) of a carbon-12 atom? why is the atomic mass of carbon listed as 12.01 amu in the table on the inside front cover of this book?

The mass of a carbon-12 atom is 12amu. The mass of carbon is listed as 12.01amu in the table in the front cover of your book because that is the average mass of carbon, this includes other carbon isotopes in the calculation such as carbon-13.

a  solution  is always transparent, light passes through with no scattering from solute particles which are molecule in size. the  solution  is homogeneous and does not settle out. a colloid is intermediate between asolution  and a  suspension. while asuspension  will separate out a colloid will not.