(a) There are 3 inclines of 1 vertical meter per 42 horizontal meters. The total vertical distance of each part of the zigzag is 209/3 ≈ 69.67 m. Therefore, the horizontal part of each zigzag is
69.67 ×42 ≈ 2926 m, and the distance along each hypotenuse, or the distance of the train
track, is