these are more clear and include numbers, thank you in advance!

1. An unknown hydrocarbon with the molecular formula C2H2 is treated with one equivalent of lithium diisopropylamide (LDA) in THF. To the resulting solution was added a compound with the molecular formula C4H8O that undergoes a substitution reaction. Following work up with acid and isolation the new compound with the molecular formula C6H10O was treated with the Dess-Martin reagent in dichloromethane to yield the final product that has a molecular formula of C6H8O. Using the IR spectra on the next page, deduce the structure of the starting material, the intermediate product, and final product in the reaction. (6 pts) 2. The substitution reaction between the C2H2 anion and the compound with the molecular formula of C4H8O occurs regioselectively. In one sentence explain what accounts for the regioselectivity. (2 pts) 3. What is unique about the central atom (responsible for the reactivity) in the Dess-Martin reagent? (2 pts) C4H8O C6H10O