E-commerce A business student conjectures that the Internet caused companies to become more profitable, since many transactions previously handled “face-to-face” could now be completed online. The...

E-commerce A business student conjectures that the Internet caused companies to become more profitable, since many transactions previously handled “face-to-face” could now be completed online. The student compares earnings from a sample of companies from the 1980s to a sample from the 2000s. Explain why this is an observational study. If indeed profitability increased, can she conclude the Internet was the cause? Why or why not?