The dentist requested that you ask the sales representative the shelf life of a particular
brand of x-ray film. You know that the
dentist wants to acquire what information?

Agroup of engineering students from purdue university reported that its licking machine, modeled after a human tongue, took an average of 364 licks to get to the center of a tootsie pop. twenty of the group's volunteers assumed the licking challenge-unassisted by machinery-and averaged 252 licks each to the center.