7 7c² c n w³

7) $$ \frac{7c^2}{n} : \frac{c}{w^3} = \frac{7c^2}{n} \cdot \frac{w^3}{c} = \frac{7c^2w^3}{cn} = \frac{7 \cdot c \cdot c \cdot w^3}{c \cdot n} = \frac{7cw^3}{n} $$

Ответ: $$\frac{7cw^3}{n}$$