An internal study by Technology Services department at Lahey Electronics revealed company employees receive the average of 4.0 emails per hour. Suppose the arrival of these emails is approximated by Poisson distribution.
a) Determine the probability Linda Lahey, company president, received exactly 4 emails between 4 P.M. and 5 P.M. yesterday? (Round your answer to 4 decimal places.)
b) Determine the probability she received 5 or more emails during the same period? (Round your answer to 4 decimal places.)
c) Determine the probability she received three or less emails during the period? (Round your answer to 4 decimal places.)