Answer
$10$
Work Step by Step
Recall:
$\log_a{\left(a\right)}=1$
Using the rule above, and knowing the natural logarithms has base $e$, gives:
\begin{align*}
10\ln{\left(e\right)}&=10\log_e{\left(e\right)}\\
&=10(1)\\
&=10
\end{align*}