Text: Based on a review of the trajectory charts in The Physics of Baseball and Keep Your Eye on the  The Science and Folklore of Baseball , conversations with University of Puget Sound physicist Andrew Rex, and correspondence with aerospace engineer and baseball researcher Roger Hawks, I determined that the McGwire home run would have traveled about 474 feet.
Entailment: I have been able to calculate the distance travel of the McGwire home run.
Contradiction: I have been able to calculate the distance travel of the McGwire home run, which is about 30 feet.