Ответ:

а) \(\frac{x^2-xy}{9y^2}:\frac{2x}{3y}=\frac{x(x-y)}{9y^2}\cdot\frac{3y}{2x}=\frac{x-y}{6y}\).

б) \(\frac{2a^3-a^2b}{36b^2}\cdot\frac{2a-b}{9b^3}=\frac{a^2(2a-b)}{36b^2}\cdot\frac{2a-b}{9b^3}=\frac{a^2(2a-b)^2}{324b^5}\).

в) \((m^2-16n^2):\frac{3m+12n}{mn}=(m-4n)(m+4n)\cdot\frac{mn}{3(m+4n)}=\frac{mn(m-4n)}{3}\).

г) \((x^2-25y^2):(x^2+10xy+25y^2)=\frac{(x-5y)(x+5y)}{(x+5y)^2}=\frac{x-5y}{x+5y}\).

д) \(\frac{c^2+4c}{c^2-4}:\frac{3c+12}{c-2}=\frac{c(c+4)}{(c-2)(c+2)}\cdot\frac{c-2}{3(c+4)}=\frac{c}{3(c+2)}\).

е) \(\frac{9p^2-1}{pq-2q}\cdot\frac{1-3p}{3p-6}=\frac{(3p-1)(3p+1)}{q(p-2)}\cdot\frac{-(3p-1)}{3(p-2)}=-\frac{(3p-1)^2(3p+1)}{3q(p-2)^2}\).