A magazine published data on the best small firms in a certain year. These were firms that had been publicly traded for at least a year, have a stock price of at least $5 per share, and have reported annual revenue between $5 million and $1 billion. The table below shows the ages of the corporate CEOs for a random sample of these firms.47,57,50,60,55,59,74,63,53,50,59,60,60,57,46,55,63,57,47,55,57,43,61,62,49,67,67,55,55,49

Use this sample data to construct a 90% confidence interval for the mean age of CEO's for these top small firms. Use the Student'st-distribution.