A study of 420,076 cell phone users found that 131 of them developed cancer of the brain or nervous system. Prior to this study of cell phone use, the rate of such
cancer was found to be 0.0224% for those not using cellphones. Complete parts (a) and (b)
a. Use the sample data to construct a 95 i dence interval estimate of the percentage of cell phone users who develop cancer of the brain or nervous system
%