2. A racing car starts from rest at the first pole and accelerates \( 0.35 \mathrm{~m} / \mathrm{s}^{2} \) for 15 seconds, continues at constant velocity for 25 seconds, and stops in the last pole in 7 sec . with constant deceleration. If the spacing between the poles is 4 meters, how many poles are there? The racetrack is parallel to the rows of poles.