Young (P) was rear-ended by Clark (D). The accident resulted when an unidentified driver pulled out of the center lane into the right-hand lane and then swerved abruptly back to the center lane causing all the drivers behind to apply their brakes. At that time, D was looking over her shoulder while attempting to change lanes and failed to see the activity ahead but was warned by a passenger and then braked but still hit P. P sued D in negligence. D denied she was negligent. The trial court submitted instructions relating to the sudden emergency doctrine. The jury found for D and P appealed.