Phenol is heated with a solution of mixture of KBr and KBrO₃.The major product obtained in the above reaction is :

Isopropylbenzene is oxidized in the presence of air to compound ‘A’. When compound ‘A’ is treated with dilutemineral acid, the aromatic product formed is

Compound ‘A’ of molecular formula C₄H₁₀O on treatment with Lucas reagent at room temperature gives compound‘B’.When compound ‘B’ is heated with alcoholic KOH, it gives isobutene. Compound ‘A’ and ‘B’ are respectively