Which of the following statements about blind spots is true?

A large vehicle such as a bus or tractor-trailer has large blind spots in front, behind, and on each side, called No-Zones. A tractor-trailer can have a 20-foot No-Zone in front and a 200-foot No-Zone in the rear. It's impossible to always avoid a large vehicle's No-Zones. However, don't remain in a No-Zone any longer than absolutely necessary.