Final answer:
E*TRADE likely utilized the percentage of sales method to set its advertising budget when it decided to buy an ad placement during the Super Bowl.
Step-by-step explanation:
E*TRADE likely utilized the percentage of sales method to set its advertising budget when it decided to buy an ad placement during the Super Bowl. This method involves allocating a certain percentage of the company's sales revenue towards advertising expenses. As the company's sales increase, the advertising budget also increases proportionally.
In this case, buying an ad placement during the Super Bowl suggests that E*TRADE was willing to invest a significant portion of its advertising budget for maximum exposure and reach. The Super Bowl is known for its large audience and high viewership, making it an attractive platform for companies to showcase their products and services.