Listed below are the commissions earned last month by a sample of 15 brokers at Sa- ( lomon Smith Barney"s Oakland, California, office. Salomon Smith Barney is an invest- II,". ment company with...

Listed below are the commissions earned last month by a sample of 15 brokers at Sa- ( lomon Smith Barney"s Oakland, California, office. Salomon Smith Barney is an invest- II,". ment company with offices located throughout the United States.

Locate the median, the first quartile, and the third quartile for the commissions earned.