Drive below the posted speed limit when: Question Drive below the posted speed limit when: Answers You see a police car. Driving on a highway where there are other cars. Anything makes conditions less than perfect. You are on a four-lane road. Explanation It is dangerous to drive at a speed too fast for conditions, regardless of the posted speed limit. Any time conditions are less than perfect, you should adjust your speed and following distance. This questions appears in the following tests: Texas Special Requirements Texas Special Requirements