Perform the Indicated Operations $\frac{2 x^{2}-x-3}{20 x^{4}-30 x^{3}} \cdot \frac{5 x^{10}+25 x^{9}-30 x^{8}}{x^{4}+5 x^{2}-6}$

Essay

Perform the indicated operations.
(a) $\frac{2 x^{2}-x-3}{20 x^{4}-30 x^{3}} \cdot \frac{5 x^{10}+25 x^{9}-30 x^{8}}{x^{4}+5 x^{2}-6}$
(b) $\frac{2}{x^{2}-2 x-3}+\frac{1}{x^{2}-7 x+12}$
(c) $\frac{u+2 v}{w-2 z}+\frac{u-2 v}{2 z-w}$
(d) $\frac{r-\frac{2}{r}}{r-\frac{1}{r}}$