hello. I am a girl and I this weekend I am doing a road race 5k and trying to break 21. I just finished my track season, so I am well trained and prepared. I have never broken 21 before; my PR is 21:20 from my 2014 fall cross country season. Do you think that this is realistic goal? If so, what should my mile splits be? I know that to break 21, it is a 6:45 average mile pace. I am just wondering what each mile should be. I have a feeling I will go out fast, slow down in the middle, but finish fast. thanks!