The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 70 and standard deviation 3 (assume the Rockwell hardness is measured on a continuous scale) a) If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness

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