"An article reported (L. Flynn, "Tax Surfing," The New York Times, March 2002, p. C10) that the mean time to download the home page for the Internal...

"An article reported (L.J. Flynn, "Tax Surfing," The New York Times, March 2002, p. C10) that the mean time to download the home page for the Internal Revenue Service, www.irs.gov, is 0.8 second. Suppose that the download time is normally distributed, with a standard deviation of 0.2 second. What is the probability that a download time is a) less than 1 second?b) between 0.5 and 1.5 second?c) above 0.5 second?d) above how many seconds are 99% of the download times?"