The mechanism of S_N1 reaction is given as :
A student writes general characteristics based on the given mechanism as :
(a) The reaction is favoured by weak nucleophiles.
(b) R⁺ would be easily formed if the substituents are bulky.
(c) The reaction is accompanied by racemization.
(d) The reaction is favoured by non-polar solvents.

The major product obtained from E₂ - elimination of 3-bromo-2-fluoropentane is

Consider the reaction sequence given below:
Which of the following statements is true?

Which of the following compunds will show retention in configuration on nucleophilic substitution by OH^– ion?