7. A student sets up an experiment using a linear air track as shown pulley light gate card vehicle small holes linear stopclock air track thread timer hanging mass 0-75 m floor not to scale A vehicle is mounted on the track. Air is blown into the track and out through small holes in the sides of the track, causing the vehicle to be lifted slightly above the track. The vehicle is released from rest and the card mounted on it passes through the light gate. State the measurements the student must make in this experiment to determine the acceleration of the vehicle. b) The student carries out the experiment using a range of hanging masses. The results are shown in table Mass of hanging mass (kg) Weight of hanging mass (N) Acceleration of vehicle (ms) 0-02 0-20 0-40 0-04 0-39 0-79 0-06 0-59 1-21 0-08 0-78 1-80 0-10 0-98 2-01 The student identifies that one of their values of acceleration needs to be measured again. State which value of acceleration needs to be measured again? Justify your answer.