Solve for $t.$

$e^{-0\mathrm{.}24t}=0\mathrm{.}39$

Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

A$.$ The solution is $t=$

$($Type an integer or a decimal. Do not round until the final answer. Then round to four decimal places as needed. Use a comma to separate answers as needed.$)$

B$.$ The solution is not a real number.