Following is a sample of unemployment rates (in percentage points) in a country sampled from the period 1990-2004. (Round your answers to two decimal places.)

4.4,4.7,5.5,5.7,4.9

(a)

Compute the mean and standard deviation of the given sample.

mean ? percentage points -

standard deviation ? percentage points -

(b)

Fill in the blanks.

Assuming that the distribution of unemployment rates in the population is symmetric and bell shaped, 95% of the time, the unemployment rate is between ? and ? percentage points.