Question When backing a truck, you should: Answers Only use the side mirrors on the driver’s side. Use both side mirrors. Never use a helper. Explanation Backing a commercial motor vehicle is always dangerous because you cannot see everything behind you. When backing, make frequent checks of the mirrors on both sides of the vehicle. Use a helper whenever possible. Take a FREE Practice Test Now This questions appears in the following tests: Alaska Knowledge Test Class A , Idaho Knowledge Test Class B ,