Question Combination vehicles: Answers Are usually shorter than single commercial vehicles. Usually require less skill to drive than single commercial vehicles. Usually require more skill to drive than single commercial vehicles. Explanation Driving combination vehicles requires more skill than driving single commercial vehicles. Combinations are generally longer, generally heavier, and are more vulnerable to rollover. This questions appears in the following tests: Alaska Tank Arizona Combination Idaho Combination Iowa Combination Iowa Combination Nevada Combination Oklahoma Combination Vermont Combination