For each of the following reactions, circle the mechanism(s) you would expect to see and provide the major product(s). Write NR for no reaction, if you don’t expect any reaction. The image presents a series of chemical reactions, illustrating mechanisms and reaction pathways involving nucleophilic substitutions (S_N1 and S_N2) and elimination reactions (E1 and E2).**Diagram (a):**- Reactants: A cyclohexyl chloride compound with a bulky base, DBN (1,5-diazabicyclo[4.3.0]non-5-ene).- Products: Not explicitly shown, but the boxed mechanisms to the right indicate the possible pathways: S_N1, S_N2, E1, or E2.**Diagram (b):**- Reactants: A linear alkyl iodide compound with sodium hydrogen sulfide (NaSH).- Products: Not explicitly shown, but the boxed mechanisms suggest pathways via S_N1, S_N2, E1, or E2.**Diagram (c):**- Reactants: A cycloalkyl bromide with sodium methoxide (Na^+ OCH_3^-).- Products: Similar to the others, potential reaction pathways include S_N1, S_N2, E1, or E2 as indicated in the box.**Diagram (d):**- Reactants: An alkyl bromide with methanol (CH_3OH) at 25°C.- Products: Again, potential mechanisms include S_N1, S_N2, E1, or E2 as shown in the box.Each reaction scheme displays the reactants followed by an arrow leading to a box. Each box categorizes the potential reaction pathways, demonstrating the flexibility in organic mechanisms and the influence of factors like the nature of the base, leaving groups, and reaction conditions.

We know that all bulky bases leads to the Hoffman product via E2 mechanism . At lower temperature substitution reaction takes place while at higher temperatures elimination reactions take place. Hard nucleophile favours E2 while soft nucleophile favours SN2. Strong base favours E2 .