Выполни деление

а) \(\dfrac {12a^3}{7b^2} : \dfrac{4a}{21b} =\) [ ];

б) \(\dfrac {2x^2y}{5} : \dfrac {5x}{2y} =\) [ ];

в) \(27c^4d : \dfrac{9cd}{2} =\) [ ];

г) \(\dfrac {15m^3n}{8} : 3m^2 =\) [ ];

д) \(\dfrac {22ay^4}{3p^2} : (-11a^2y) =\) [ ].