===========================================================
$\small \left[\left(-\dfrac{3}{4}\right)^{-2}\right]^2÷\left[\left(-\dfrac{3}{4}\right)^2·\left(-\dfrac{3}{4}\right)^{-3}÷\left(-\dfrac{3}{4}\right)^{-2}\right] =$
$\small = \left(-\dfrac{3}{4}\right)^{-2·2}÷\left[\left(-\dfrac{3}{4}\right)^{2+(-3)-(-2)}\right] =$
$\small = \left(-\dfrac{3}{4}\right)^{-4}÷\left(-\dfrac{3}{4}\right)^{2-3+2} =$
$\small = \left(-\dfrac{4}{3}\right)^4÷\left(-\dfrac{3}{4}\right)^1 =$
$\small = \left(-\dfrac{4}{3}\right)^4·\left(-\dfrac{4}{3}\right)^1 =$
$\small = \left(-\dfrac{4}{3}\right)^{4+1} =$
$\small = \left(-\dfrac{4}{3}\right)^5 $
$\small =\left(-\dfrac{1024}{243}\right).$