(IT) A 1. 0 x 10^3 kg Toyota collides into the rear end of a 2. 2 x 10^3-kg Cadillac stopped at a red light. The bumpers lock, the brakes are locked, and the two cars skid forward 2. 8 m before stopping. The police officer, knowing that the coefticient of kinetic fric- tion between tires and road 1s 0. 40, calculates the speed of the Toyota at impact. What was that speed?