Answer:

Given:
Initial speed (u) = 65 km/h
Final speed (v) = 85 km/h
Acceleration (a) = 80 km/h²
To Find:
Time taken for car to achieve a speed of 85 km/h in minutes
Explanation:


By substituting value of v, u & a we get:

Substract 65 from both sides:



Dividing both sides by 80:






So,
Time taken for car to achieve a speed of 85 km/h in minutes = 15 minutes