List three largest American companies of 2015.

List three largest American companies of 2015.
【正确答案】：In 2015, the 10 largest American companies by market capitalization were Apple, Google, ExxonMobil, Berkshire Hathaway, Microsoft, Wells Fargo, Johnson, Walmart, General Electric, and Facebook.(Choose three for answer)
【题目解析】：
参见教材P237。