The number of spam emails received each day follows a Poisson distribution with a mean of 50. Approximate the following probabilities. Round your answer to four decimal places (e.g. 98.7654).
(a) More than 30 and less than 60 spam emails in a day.
(b) At least 30 spam emails in a day.
(c) Less than 30 spam emails in a day.
(d) Approximate the probability that the total number of spam emails exceeds 330 in a seven-day week.