Twoâ cars, 405 kilometersâ apart, begin driving toward each other on aâ long, straight highway. one car travels 70 kilometers per hour and the other 65 kilometers per hour. at the sameâ time, aâ canary, starting on oneâ car, flies back and forth between the two cars as they approach each other. if the canary flies 100 kilometers per hour and spends no time to turn around at eachâ car, how far has it flown when the carsâ collide?