Which of the following is not a macromolecular colloid?

All colloidal dispersions have

Equal volumes of two $AgI$ sols are mixed together. The first sol is obtained by adding $AgNO_3$ to a slight excess of $KI$,and the second sol is obtained by adding $KI$ to a slight excess of $AgNO_3$. What happens when they are mixed?

Bredig's arc method cannot be used to prepare a colloidal solution of which of the following?

What happens when dialysis is prolonged?

The number of colloidal systems from the following,which will have 'liquid' as the dispersion medium,is $.........$.
Gem stones,paints,smoke,cheese,milk,hair cream,insecticide sprays,froth,soap lather.