д) \(\sqrt{2\frac{7}{9}}\) ;

д) \(\sqrt{2\frac{7}{9}} = \sqrt{\frac{2 \cdot 9 + 7}{9}} = \sqrt{\frac{18 + 7}{9}} = \sqrt{\frac{25}{9}} = \frac{\sqrt{25}}{\sqrt{9}} = \frac{5}{3} = 1\frac{2}{3}\)

Ответ: \(1\frac{2}{3}\)