The human resources group regularly interviews prospective clerical employees and tests their skill at data entry. The following table shows the number of errors made by 60 prospective clerks when entering a form with 80 numbers. (Five clerks made 4 errors.) Test the null hypothesis that the number of errors follows a Poisson distribution. Find the

(a) Rate (or mean) of the Poisson distribution.
(b) Expected number of employees who make no mistake.
(c) Degrees of freedom for x2.
(d) x2.
(e) p-value for testing H0.

# Errors # Clerks 12 20 14 4 or more 5