Answer:
a) y^9 * y^5 = y^(9 + 5) = y^ 14
b) r^13 * r^11 * r^7 = r^(13 + 11 + 7) = r^ 31
c) (18^9)^3 = (18 )^9^3 = 18 ^ 27
Part A:
We use the property of the exponents that whenever we are multiplying two numbers with exponent with the same base, their powers add.
[tex]y^9\cdot y^5=y^{9+5}=y^{14}[/tex]Part B:
We use the same property used in part A.
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