Many of the world’s most successful companies rely on The NPD Group to provide global sales and marketing information that helps clients make more informed, fact-based decisions to optimize their businesses. These customers need NPD help for insight on what is selling, where, and why so that they can understand and leverage the latest trends. They recently (July 2009) released the following results of a survey intended to determine the market share distribution for the major corporations that make digital music devices:

a. Generate a bar chart to display these data.
b. Generate a pie chart to display these data.
c. Which of the two displays most effectively presents the data? Explain your answer.