5.34 Упростите выражение:

a) $$-21 \cdot x \cdot (-4) = 84x$$ б) $$-7.9 \cdot 10 \cdot y = -79y$$ в) $$8 \cdot (-2.5) \cdot n = -20n$$ г) $$a \cdot (-0.5) \cdot 4.4 = -2.2a$$ д) $$-4.1 \cdot x \cdot (-4) = 16.4x$$ е) $$\frac{8}{11} \cdot n \cdot (-22) = -16n$$ ж) $$\frac{7}{9} \cdot x \cdot (-1\frac{1}{7}) = \frac{7}{9} \cdot x \cdot (-\frac{8}{7}) = -\frac{8}{9}x$$ з) $$-1\frac{5}{6} \cdot m \cdot \frac{6}{11} = -\frac{11}{6} \cdot m \cdot \frac{6}{11} = -m$$ и) $$0.16 \cdot t \cdot (\frac{3}{8}) = \frac{16}{100} \cdot t \cdot \frac{3}{8} = \frac{2}{25} \cdot t \cdot \frac{3}{1} = \frac{6}{25}t = 0.24t$$