The internal revenue service reports that the mean federal income tax paid in the year 2010 was $8040.Assume that the standard deviation is 4600.

The internal revenue service reports that the mean federal income tax paid in the year 2010 was $8040. Assume that the standard deviation is 4600. The IRS plans to draw a sample of 1000 tax returns to study the effect of a new tax law. What is the probbility that the sample mean tax is less than 8100. Round answer to four decimal places.