a) (2/3)⁻² = (3/2)² = 9/4 = 2.25
б) (4 ⋅ 27)⁻¹ = (108)⁻¹ = 1/108
в) (-1/8 ⋅ 36)⁻² = (-36/8)⁻² = (-9/2)⁻² = (-2/9)² = 4/81
г) (-4/9)⁻¹ = -9/4 = -2.25
д) (1 2/3)⁻² = (5/3)⁻² = (3/5)² = 9/25 = 0.36
е) (7 ⋅ 1/4)⁻¹ = (7/4)⁻¹ = 4/7