Draw all products, including stereoisomers, in each reaction.

a.

b.

c.

d.

Weak bases and weak nucleophiles such as water and methanol promote a mixture of both ${\mathbf{\text{S}}}_{\mathbf{\text{N}}}\mathbf{\text{1}}$ and E1 reactions.Both water and methanol are weak bases and weak nucleophiles.

Tertiary halides undergo a ${\text{S}}_{\text{N}}\text{1}$ and E1 reactions respectively when a weak nucleophile and a weak base are used, which is observed for reactions (c).

Based on all the points, the products formed, including their stereoisomers, are as follows:

All the major elimination products are considered here.

Representation of all the substituted and eliminated products from a

Representation of all the substituted and eliminated products from b

Representation of all the substituted and eliminated products from c

Representation of all the substituted and eliminated products from d