2)-풍: (-옴)=

г) $$-\frac{5}{8} : (-\frac{9}{10}) = \frac{5}{8} : \frac{9}{10} = \frac{5}{8} \cdot \frac{10}{9} = \frac{5 \cdot 10}{8 \cdot 9} = \frac{50}{72} = \frac{25}{36}$$

Ответ: $$\frac{25}{36}$$