The manager for a radio station wants to estimate the mean length of all songs published after 1960. How many songs should be in the sample if we want 90% confidence that the sample mean is within 15 seconds of the population mean? Assume that s = 2.625 minutes. (Hints: Watch the units here (they need to be consistent) and remember the rounding rules for sample sizes). (Round to three decimals)

Sample size required: ______