SEC. 89.21. RIGHT OF ROADWAY.

   Upon all roadways a vehicle shall be driven upon the right half of the roadway, except as follows:

   (a)   When overtaking and passing another vehicle proceeding in the same direction under the rules covering such movement.

   (b)   When placing a vehicle in a lawful position for, and when the vehicle is lawfully making a left turn.

   (c)   When the right half of the roadway is closed to traffic.

   (d)   Upon a roadway designated. and sign posted for one-way traffic.

   (e)   When the roadway is not of sufficient width.

SEC. 89.22. TURNING IN INTERSECTION.

   The driver of a vehicle intending to turn at an intersection shall do so as follows:

   (a)   Right turns. Both the approach for a right turn and a right turn shall be made as close as practicable to the right-hand curb or edge of the roadway.

   (b)   Left turns. The driver of a vehicle intending to turn left at any intersection shall approach the intersection in the extreme left lane lawfully available to traffic moving in the direction of the driver of such vehicle and after entering the intersection the left turn shall be made so as to leave the intersection in a lane lawfully available to traffic moving in such direction upon the roadway being entered.

SEC. 89.23. ONE-WAY TRAFFIC.

   No person shall operate or move a vehicle upon any roadway designated and sign posted for one-way traffic in a direction opposite to that indicated by the designation or sign post.

SEC. 89.24. LANED ROADWAY.

   Whenever any roadway has been divided into two or more clearly marked lanes for traffic, a vehicle shall be driven as near as practicable entirely within a single lane and shall not be moved from the lane until the driver has first ascertained that such movement can be made with reasonable safety.

SEC. 89.25. STARTING PARKED VEHICLES OR BACKING.

   No person shall start a vehicle stopped, standing or parked on a roadway, nor shall any person back a vehicle on a roadway until such movement can be made with reasonable safety.

SEC. 89.26. TURNING MOVEMENTS AND REQUIRED SIGNALS.

   No person shall turn a vehicle from a direct crossing or move right or left upon a roadway until such movement can be made with reasonable safety and then only after the giving of an appropriate signal in a manner provided in this division in the event any other vehicle may be affected by the movement.