Why is it dangerous to evaluate media solely based on CPM? It doesn't take into account the circulation of the media. Costs can vary among different advertisers, based on the number of buys. O Most media don't have accurate information on how many people they reach. O Media differ vastly in their abilities to communicate information. How does the bounce rate give context to clickthrough rates? O It identifies customers who decided to visit a competitive website. The bounce rate is important in robotic bidding for search engine marketing (SEM). O It sets aside site visitors who reached a website by mistake or found the content uninteresting. The bounce rate is deducted from the clickthrough rate when advertisers pay for traffic driven to their website