CEMC Fermat, 2002

Number theory Difficulty 2.0 Junior Find the answer Canada

If $2^a 3^b = 8\left(6^{10}\right)$ , where $a$ and $b$ are integers, then $b-a$ equals

(A) $0$ (B) $23$ (C) $-13$ (D) $-7$ (E) $-3$

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