Given, Total time = 2 minutes 20 seconds

= 2 × 60 + 20

= 120 + 20

= 140 seconds

As in 40 s,

The number of rounds completed = 1

Now we have to find the number of rounds completed in 140 seconds:

So, In 140 s, the number of rounds completed = × 140

= 3.5

(a) Diameter of circular track = 200m

_{Radius of circular track, (r) = 100m}

Now, Distance covered in 1 round = Circumference of the circular track

= 2πr

= 2 × × 100 m

= 628.57 m

And,

Distance covered = 628.57 × 3.5 m

So, in 3.5 rounds the total distance covered = 2200 m

(b) As the athlete makes 3.5 rounds of the circular track and if he starts from point A then after completing the 3 rounds he will be at the same point A. On starting again from the same point and makes the remaining half round he will reach at the point B. Therefore, the displacement of the athlete will be equal to the diameter of the track i.e., 200m.