An enthusiast wants to measure the average speed of a model speedboat along a straight section of a canal.
To estimate the distance, they count the number of brick pillars on a canal-side wall between the start and finish lines. They estimate each pillar is spaced 2.0 m apart and count 12 pillars.
To measure the time taken for the speedboat to travel this distance, they use a manual stopwatch on a smartphone, starting it when the boat passes the first pillar and stopping it when it passes the twelfth pillar.
State two improvements the enthusiast could make to this method to get a more accurate value for the average speed.