Compound A was converted to compound B by the sequence shown. It is likely that the first...

Compound A was converted to compound B by the sequence shown. It is likely that the first step in this sequence gives two isomeric products having the molecular formula C₁₀H₁₅BrO₂, and both of these give compound B in the second step.

(a) Suggest reasonable structures for the two isomers of C₁₀H₁₅BrO₂ formed in the first step.

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(b) Give a mechanistic explanation why both isomers give the same product in the second step.