To rewrite the expression \( 6^{-3} \cdot 6^5 \) using a single exponent, you can use the property of exponents that states \( a^m \cdot a^n = a^{m+n} \).
Applying this property:
\[ 6^{-3} \cdot 6^5 = 6^{-3 + 5} = 6^{2} \]
So, the expression simplifies to:
\[ 6^{2} \]