that's how many siblings joined the high i.q. club mensa. the quadruplets of texas are 17 years old and to join the club, the i.q.'s have to be higher than 98% of the united states. >> look forward to seeing them. >> speaking of high i.q.'s, all time "jeopardy!" champ ken jennings has proven he's a tough opponent for any man or woman. >> what's america the beautiful? what are the yellow pages? >> ken? >> who are the power rangers. >> what is on the town. >> what's a gastropod? >> what about a computer opponent? >> watson? >> who is c. s. lewis. >> yes. >> watson sf>> what is cactus? >> yes. >> who is henry viii. >> this showdown isn't over. he has one more chance to beat watson the machine.