A computer company produced this graph to show how many computers it expects to sell based on how much the company spends on Internet advertising. The company expects to sell 40 million computers, spending $5 million on Internet advertising. Which set of units and scales are appropriate for the two axes? Horizontal axis: Number of Computers (in millions); Vertical axis: Advertising Dollars (in tens of millions) 60 50 Horizontal axis: Number of Computers (in millions): Vertical axis: Advertising Dollars (in millions) 40 30 20 Horizontal axis: Advertising Dollars (in millions); Vertical axis: Number of Computers (in millions) 10 0 1 2 3 4 5 6 Horizontal axis: Advertising Dollars (in millions): Vertical axis: Number of Computers (in tens of millions)​