In a study of 474,508 cell phone​ users, it was found that 197 developed cancer of the brain or nervous system. Assuming that cell phones have no​ effect, there is a XXXXXXXXXX probability of a person...

In a study of

cell phone​ users, it was found that

developed cancer of the brain or nervous system. Assuming that cell phones have no​ effect, there is a

probability of a person developing cancer of the brain or nervous system. We therefore expect about

cases of such cancer in a group of

people. Estimate the probability of

or fewer cases of such cancer in a group of

people. What do these results suggest about media reports that cell phones cause cancer of the brain or nervous​ system?

​(a)