Give the sterochemical products of the following `:`
`a.`
`b.`
`c.`
`d.`

Explanation

`a.` First, addiction of electrophile `Br^(o+)` and then attack by a nucleophile `(H_(2)O)` take place in anti`-` Markovnikov manner and then deprotonation by `H_(2)O`.

`b.`
Reactant cis or trans (iwith two different groups)+ reagent `HBr` addition is anti (ith different groups) `implies` product is always racemic.
Reaction is stereospecific (addiction of reagent is specific, i.e., anti) and non`-` stereoselective also (since two compounds are obtained in equal amount).

c
First, electrophile `(Cl^(o+))` atack and then nucleophile `(H_(2)O)`, as explained in the mechanism.
d
All the addition are anti or trans and are also said to be antarafacial, `i.e.,` the groups are added (first electrophile and then nucleophile) from opposite faces of the double bond.