1). In 1992, the Journal of Epidemiology and Community Health published an article that claimed that the average incubation period from infection with HIV to the development of AIDS was 6.7 years with a standard deviation of 4.3 years. Complete the following steps to determine the probability that in a sample of 520 infected individuals, the sample mean is between 6.4 and 6.8years. (z-scores have two decimal places and areas/probabilities have four)

Insert the following values from the question:

=_____years

=_____years

n =_____individuals

What is the first z-score?_____

What is the second z-score?_____

What are the areas?____________

What is the probability that the sample mean is between 6.4 and 6.8 years?______