In the aftermath of the emissions scandal, the blue book value of any Volkswagen vehicle decreased by:

here are the answers to your questions:

6. The correct option is About 15 percent.
In the aftermath of the Volkswagen emissions scandal, the resale value (blue book value) of affected Volkswagen diesel vehicles saw a significant decrease, with many reports indicating a drop of around 15% or more.

7. The correct option is True.
Martin Winterkorn, who was the CEO of Volkswagen Group at the time the emissions scandal broke in September 2015, resigned from his position shortly after the news became public.