Find the number of standard deviations from the mean. Round to the nearest hundredths.
The average number of days absent per student per year at West Valley School is 17 days with a standard deviation of 4 days. How many standard deviations from the mean is 6 absent days?
a. About 2.17 standard deviations below the mean
b. About 2.17 standard deviations above the mean
c. About 2.75 standard deviations above the mean
d. About 2.75 standard deviations below the mean
e. About 0.67 standard deviations above the mean