Which of the following compounds has the highest boiling point?

What is the bond length between carbon and bromine in $CH_3Br$ molecule (in $pm$)?

In the above reaction,the major product '$P$' is:

$A$ haloalkane undergoes $S_{N}2$ or $S_{N}1$ reaction depending on

Which one of the following is likely to give a precipitate with $AgNO_3$ solution?

The order of $S_N 1$ reactivity in aqueous acetic acid solution for the compounds:
$1$. $CH_3-CO-CH_2-Cl$
$2$. $CH_3-CH_2-CH_2-Cl$
$3$. $(CH_3)_3C-Cl$
is