The well-known, and daunting, statistic relevant to this entrepreneurial series is that an estimated 90 percent of all new businesses fail in their first year. Perhaps an acute awareness of that is what’s behind tonight’s episode, a cheery celebration at having reached episode number 100 in the cutthroat world of network television. Tonight, for the first time on this series, all six sharks will be swimming in the same TV pool simultaneously. They will not, however, be equipped with laser beams.