Presented here is selected information from the 2017 fiscal-year 10-K reports for four companies. The four companies, in alphabetical order, are Advance Micro Devices, a global semiconductor company; AT&T, Inc., a company that provides communications and digital entertainment; Caterpillar, Inc., a manufacturer of heavy machinery; and Pfizer, Inc., a pharmaceutical manufacturer. The data for the companies, presented in the order of the amount of their sales in millions of dollars, are:

Based on these financial data and your knowledge and assumptions about the nature of the businesses that the companies operate, determine which data relate to which companies. Write a memorandum explaining your decisions. Include a discussion of which ratios you used in your analysis, and show the computations of these ratios in your memorandum. Hint: calculate Gross Margin, Return on Sales, Return on Assets.

\begin{tabular}{|lrrrr|} \hline & \multicolumn{1}{c}{ A } & B & \multicolumn{1}{c}{ C } & \multicolumn{1}{c|}{ D } \\ Sales & $5,329 & $45,462 & $52,546 & $160,546 \\ Cost of goods sold & 3,506 & 31,049 & 11,240 & 77,379 \\ Net earnings & 43 & 754 & 21,307 & 29,450 \\ Inventory & 739 & 10,018 & 7,578 & - \\ Accounts receivable & 400 & 16,193 & 8,221 & 16,522 \\ Total assets & 3,540 & 76,962 & 171,797 & 444,097 \\ \hline \end{tabular}