Which compounds give $\beta$-elimination reactions? What are their main products?

Consider the following reaction,
$C_2H_5Cl + AgCN \xrightarrow{EtOH / H_2O} \underline{X} \text{ (major)}$
Which one of the following statements is true for $\underline{X}$?
$(I)$ It gives propionic acid on hydrolysis
$(II)$ It has an ester functional group
$(III)$ It has a nitrogen linked to ethyl carbon
$(IV)$ It has a cyanide group

Which one of the following halogen compounds is not useful as a substrate in an $S_N2$ reaction?

Which of the following statements is correct for the reactivity in $S_N2$ reaction?

What is the product formed by the reaction of $2-$methylpropene with $HBr$ in the presence of peroxide?

The reaction of carbon tetrachloride with water vapor at $500\,^oC$ gives .................