all of this was an act of pure impulse , the missile sought for , found , and thrown before she had time to ensure the failure of the shot by reflecting on how unlikely it was that a woman who had gotten a d in the archery mod of her two-year college phys ed requirement could possibly hit a dog with an ashtray , especially when the dog was fifteen feet away and the hand she was throwing with happened to be handcuffed to a bedpost .