Because of the relatively high interest rates, most consumersattempt to pay off their credit card bills promptly. However, thisis not always possible. An analysis of the amount of interest paidmonthly by a bank's Visa cardholders reveals that the amount isnormally distributed with a mean of 30 dollars and a standarddeviation of 9 dollars.
A. What proportion of the bank's Visa cardholders pay more than34 dollars in interest?
B. What proportion of the bank's Visa cardholders pay more than39 dollars in interest?
C. What proportion of the bank's Visa cardholders pay less than21 dollars in interest?
D. What interest payment is exceeded by only 19% of the bank'sVisa cardholders?