Lara is calculating the standard deviation of a data set that has 8 values. she determines that the sum of the squared deviations is 184. what is the standard deviation of the data set? round the answer to the nearest tenth. enter your answer in the box.

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?