The amount of time that customers wait in line during peak hours at one bank is normally distributed with a mean of 13 minutes and a standard deviation of 3 minutes. The percentage of time that the waiting time lies between 11 and 13 minutes is equal to the area under the standard normal curve between ___and ___.
a).62, .77
b) -.67,0
c)-2, 0
d) 0, .67