\[C{{H}_{3}}C{{H}_{2}}Cl\xrightarrow{NaCN}X\xrightarrow{Ni/{{H}_{2}}}Y\xrightarrow[\text{anhydride}]{\text{Acetic}}Z\]
$$Z$$ in the above reaction sequence is

Solution :
\[\begin{align} & C{{H}_{3}}C{{H}_{2}}Cl\xrightarrow{NaCN}\underset{\left( X \right)}{\mathop{C{{H}_{3}}C{{H}_{2}}CN}}\,\xrightarrow{Ni/{{H}_{2}}} \\ & \underset{\left( Y \right)}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}N{{H}_{2}}}}\,\xrightarrow[{{\left( C{{H}_{3}}CO \right)}_{2}}O]{}\underset{\left( Z \right)}{\mathop{C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}NHCOC{{H}_{3}}}}\,+C{{H}_{3}}COOH \\ \end{align}\]