(5x /3y )^2 * 4y^5 /5x^4 = 25х^2/9у^2 * 4y^5/5x^4 = 25х^2 * 4y^5 / 9y^2 * 5x^4 = 5*4y^3 / 9x^2 = 20y^3 / 9x^2
(xy^3 /z ^2)^2 * z^3 /xy^7 = x^2*y^6 / z^7 * z^3/ xy^7 = x/zy
(5x /3y )^2 * 4y^5 /5x^4 = 25х^2/9у^2 * 4y^5/5x^4 = 25х^2 * 4y^5 / 9y^2 * 5x^4 = 5*4y^3 / 9x^2 = 20y^3 / 9x^2
(xy^3 /z ^2)^2 * z^3 /xy^7 = x^2*y^6 / z^7 * z^3/ xy^7 = x/zy