A passenger train travels round a circular section of track of radius 400 m at a speed of 72 km h⁻¹.
a. (i) Convert the train’s speed to SI units.
b. (ii) Calculate the magnitude of the acceleration directed towards the centre of the track.
c. (iii) Express this acceleration as a fraction of the acceleration due to gravity g=9.8m s−2. Round your answer to two significant figures.