Вычисли, записывая по образцу пункта а

а) \(\cfrac{6}{7}\cdot \cfrac{7}{9}=\dfrac{6\cdot 7}{7\cdot 9}=\dfrac{2\cdot 1}{1\cdot 3}=\dfrac{2}{3}\) ;

б) \(\cfrac{11}{12}\cdot \cfrac{21}{22}=\) [ ] \(=\) [ ] \(=\) [ ];

в) \(\cfrac{8}{9}\cdot \cfrac{7}{10}=\) [ ] \(=\) [ ] \(=\) [ ];

г) \(\cfrac{25}{27}\cdot \cfrac{18}{35}=\) [ ] \(=\) [ ] \(=\) [ ];

д) \(\cfrac{15}{6}\cdot \cfrac{4}{5}=\) [ ] \(=\) [ ] \(=\) [ ];

е) \(\cfrac{23}{33}\cdot \cfrac{22}{23}=\) [ ] \(=\) [ ] \(=\) [ ].