Thirty companies comprise the DJIA. Just how big are these companies? One common method for measuring the size of a company is to use its market capitalization, which is computed by multiplying the number of stock shares by the price of a share of stock. On March 29, 2010, the market capitalization of these companies ranged from Alcoa's $14.7 billion to ExxonMobil's $318.8 billion. The entire population of market capitalization values is stored in DowMarketCap.
a. Compute the mean and standard deviation of the market capitalization for this population of 30 companies.
b. Interpret the parameters computed in (a).