Two cars have collided at right angles at an intersection: Car A was eastbound; car B was northbound. The marks on the pavement show that the vehicles both moved together in the same direction immediately after the collision. That direction was at an angle of 52.3° north of east (i.e. 52.3° above the positive x-axis). It is known than car A (m = 1000 kg) was moving at 20 m/s just prior to the crash, and car B was moving at 25 m/s just prior to the crash. What was the mass of car B? Same situation as in the first part, but this time suppose you know the mass of car B (1200 kg) but not its speed prior to the collision. Find that speed.