Answer:
Roselle was able to help Michael because she was a guide dog and know-how to take Michael in and out of places, besides Michael kept calmed all the time so Roselle could focus on the exit.
Explanation:
On 9/11 Michael was working as in any other normal day in the office, and when he felt that the building was moving he thought it was an earthquake and because his sense of self-control Roselle was able to guide him and his co-worker to the exit without any harm, them both became celebrities. Michael even wrote a book about the event.
It depends on who or what the letter is for...
