1. Andrew Carnegie, whose portrait is in my office, is pissed off with me.

2. The bullet was left in the wall when the wall was put in back in 1992 or so.

3. The CIA has bullets that can go through windows without leaving a trace.

4. The bullet was on the ledge at the top of the windows (about 12 feet up) and that was its day to go BANG.

5. Lee Harvey Oswald and/or John Wilkes Booth.