explanation please

Question 4. Inspect this multistep synthetic sequence and answer the questions below. An excerpt from the 13C NMR spectrum and chemical formula of the final product has been provided on the next page as a hint. I. Provide complete structures for AE in the empty boxes above. If a reaction is expected to produce more than one product, provide a structure ONLY for the major compound. ( 2 points each) II. Provide a full arrow-pushing mechanism for CD and a brief explanation for the isomer of the product you propose. (5 points) III. Provide a full arrow-pushing mechanism for DE ( 5 points) IV. Assign the stereochemistry for ALL stereocenters in D (5 points) Two blank pages are included below for you to show your work in II-IV