Heating acetone with an excess of phenol in the presence of hydrogen chloride is the basis for an industrial process used in the manufacture of a compound called “bisphenol A.” (Bisphenol A, about which there are significant health concerns, has been used in the manufacture of epoxy resins and a polymer called Lexan.) Bisphenol A has the molecular formula C₁₅H₁₆O₂, and the reactions involved in its formation are similar to those involved in the synthesis of DDT (see “The Chemistry of . . . Aryl Halides:  Write out these reactions and give the structure of bisphenol A.