Ответ:

  1. \(\dfrac{2^3\cdot3^3}{6^2}=\dfrac{8\cdot27}{36}=\dfrac{216}{36}=6\).

  2. \(\dfrac{1.8}{(0.2)^2}+(-6)^2=\dfrac{1.8}{0.04}+36=45+36=81\).

  3. \(\left(\dfrac{-1.3-0.45}{5^2}\right)^2=\left(\dfrac{-1.75}{25}\right)^2=(-0.07)^2=0.0049\).

Ответ: а) 6; б) 81; в) 0,0049.