In all these expressions you have a power of a power.
You can solve them simply multiplying the exponents.
Remember that any quantity raised to the zero is equal to 1.
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11) (n^4)^8 = n^(4×8) = n^32
13) (q^10)^10 = q^(10×10) = q^100
15) (x^3)^-5 = x^[3×(-5)] = x^(-15)
17) (z^8)^0z^5 = z^(8×0) z^5 = z^0 z^5 = 1×z^5 = z^5
19) (c^3)^5(d^3)^0 = c^(3×5) d^(3×0) = c^15 d^0 = c^15×1 = c^15
