Diazotization

Treatment of primary amines with nitrous acid gives diazonium ions. Aliphatic diazonium ions decompose under the diazotization conditions to give complex mixture of products. Aryldiazonium ions are stable and is a valubale intermediate. They react with activated aromatic compounds to give coupling product. What would be the product of the given reaction?

Treatment of primary amines with nitrous acid gives diazonium ions. Aliphatic diazonium ions decompose under the diazotization conditions to give complex mixture of products. Aryldiazonium ions are stable and is a valubale intermediate. They react with activated aromatic compounds to give coupling product. At what pH phenol reacts with benzene diazonium chloride to give coupling product?

Aniline when diazotized in cold and then treated with dimethyl aniline gives a coloured product. Its structure would be