Freestyle rapper cracks up Simon Cowell in 'America's Got Talent' semifinals

Freestyle rapper cracks up Simon Cowell in 'America's Got Talent' semifinals

Chris Turner asked the audience to hold up items for him to use in a song that he would make up on the spot.NBC Simon Cowell laughs on Tuesday's episode of 'America's Got Talent'Simon Cowell couldn't stop laughing on Tuesday's episode of America's Got Talent, because of freestyle rapper Chris Turner's performance in the semifinals.While Turner has previously asked the judges to name subjects for him to rap about, he cranked his act up a level wh…