(a) Here, 4 squares on t-axis = 4s

1 squares = 1s

2 squares on v-axis = 2 ms^–1

1 squares = 1 ms^–1

Hence area of 1 square = 1 × 1 = 1 m from t = 0 to t = 4s, the number of squares of the region between the v-t graph and t-axis = n = 20 (more than half the squares have been considered).

Hence the distance covered by the car is 13.33 m through the dotted squares.

(b) Here the speed of car is uniform after t = 7 seconds.