A study of 420,090 cell phone users found that 135 of them developed cancer of the brain or nervous system. Prior to the study of cell phone use, the right of such cancer was found to be 0.0203% for those not using cell phones. A. Use The sample data to construct a 90% confidence interval estimate of the percentage of cell phone users who develop cancer of the brain or nervous system.

Arestaurant manager wanted to get a better understanding of the tips her employees earn, so she decided to record the number of patrons her restaurant receives over the course of a week, as well as how many of those patrons left tips of at least 15%. the data she collected is in the table below. day mon tue wed thu fri sat sun patrons 126 106 103 126 153 165 137 tippers 82 87 93 68 91 83 64 which day of the week has the lowest experimental probability of patrons tipping at least 15%? a. sunday b. saturday c. friday d. thursday