Which of the following will have an enantiomer?

Which one of the following is more readily hydrolysed by $S_{N}1$ mechanism?

The order of $S_{N^1}$ reactivity in aqueous acetic acid solution for the compounds:
$(1)$ $CH_3-CO-CH_2-Cl$
$(2)$ $CH_3-CH_2-CH_2-Cl$
$(3)$ $(CH_3)_3C-Cl$

What would be the effect of increasing solvent polarity on the rate of each of the following reactions? ($Nu =$ neutral nucleophile)
$A. Nu + R-L \to Nu^{+}-R + L^{-}$
$B. R-L \to R^{+} + L^{-}$

The order of reactivity of the given haloalkanes towards nucleophiles is:

Identify the correct decreasing order of reactivity of alkyl halides with ammonia.