Ответ:

9^10=9^1*9^9

(2/3)^8 = (2/3)^2*(2/3)^6

81,4^6=81,4^0*81,4^6

(-4/11)^15=(-4/11)^7*(-4/11)^8

(-20)^7=(-20)^2*(-20)^5

(5 1/9)^40=(5 1/9)^20*(5 1/9)^20

(-0,09)^13=(-0,09)^10*(-0,09)^3

(-2 5/13)^28 = (-2 5/13)^1*(-2 5/13)^27