Ответ:

  1. \(\frac{13a}{b^{-3}}\cdot\frac{b}{52a^{-5}}=\frac{13}{52}a^{1+5}b^{3+1}=\frac14a^6b^4\).
  2. \(\left(\frac{12x^{-1}}{5y}\right)^{-2}\cdot72x^{-5}y^2=\left(\frac{12}{5xy}\right)^{-2}\cdot72x^{-5}y^2=\left(\frac{5xy}{12}\right)^2\cdot72x^{-5}y^2=\frac{25x^2y^2}{144}\cdot72x^{-5}y^2=\frac{25y^4}{2x^3}\).

Ответ: 1) \(\frac14a^6b^4\); 2) \(\frac{25y^4}{2x^3}\).