You have submitted your vacation plans to your boss. The request must be approved by your boss, and the amount of time s

[answerhappygod]

You have submitted your vacation plans to your boss. The request
must be approved by your boss, and the amount of time she takes to
review the request is exponentially distributed with mean 3 days.
After that, she submits them to her boss, who must also approve it,
and this amount is also exponentially distributed with mean 3 days.
Assuming they both approve your request, determine the probability
of getting approval from both of them in 5 days or less.