1. n^3/n^5

2. (2b)^3(b^-4)

3. (mn)^2 ∙ n^4

4. 3a^5 ∙ 5a^-2 ∙ a^3

5. (x^3/xy^4) ∙ (y/x)^5

6. (a^-1)(b^2)/ab ∙ (a^2)(b^3)/b^-2

Great summary page here

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