Business: Advertising It has been estimated that the number of people who will see a new...

Business: Advertising It has been estimated that the number of people who will see a newspaper advertisement that has run for x consecutive days is of the form , where T is the total readership of the newspaper. If a newspaper has a circulation of 400,000, an ad that runs for x days will be seen by people. Find how fast this number of potential customers is growing when this ad has run for 5 days.