Standing alongside a straight section of railroad track as a train passes, you record the sound of the train's horn. By analyzing the recording, you determine that the frequency of the sound was \(483 \mathrm{~Hz}\) as the train approached and \(405 \mathrm{~Hz}\) after it passed. At what speed was the train moving? Use \(343 \mathrm{~m} / \mathrm{s}\) for the speed of sound in air. Assume that the train starts out coming almost straight at you and ends up moving almost directly away from you.