### Exercise condition:

3
(i) $\left(\frac{-4}{4}×\frac{1}{4}\right)$ is .

(ii) $\left(\frac{-4}{4}×\frac{-8}{7}\right)=\left(\frac{-8}{7}×\frac{-4}{4}\right)$ is .

(iii) $\left(\frac{-15}{4}+\frac{7}{7}\right)+\frac{1}{6}=\frac{-15}{4}+\left(\frac{7}{7}+\frac{1}{6}\right)$ is .