See image — AITS & Test Series Chemistry Question

💡 Solution & Explanation

Draw the bond line structure of each molecule you will get to know (P, Q) and (R, S) Represents different set of molecules while Q and R are same molecules. All the given molecules has no chiral centre so all are achiral. None of the molecule will be oxidized by acidic potassium dichromate solutions as all are tertiary alcohols.