A car travels with a uniform velocity of 20 m `s^(-1)` for 5 s. The brakes are then applied and the car is uniformly retarded. It comes to rest in further 8 s. Draw a graph of velocity against time. Use this graph to find :
(i) the distance travelled in first 5 s,
(ii) the distance travelled after the brakes are applied,
(iii) total distance travelled, and
(iv) acceleration during the first 5 s and last 8 s.

Explanation

To solve the problem step by step, let's break it down according to the parts of the question.

### Step 1: Draw the Velocity-Time Graph
1. **Draw the axes**: The vertical axis represents velocity (in m/s), and the horizontal axis represents time (in seconds).
2. **Plot the first segment**: From 0 to 5 seconds, the car travels with a uniform velocity of 20 m/s. This is represented as a horizontal line at 20 m/s from t = 0 to t = 5.
3. **Plot the second segment**: From 5 seconds to 13 seconds (5 + 8 seconds), the car comes to rest uniformly. The velocity decreases from 20 m/s to 0 m/s over 8 seconds. This is represented as a straight line sloping downwards from (5, 20) to (13, 0).

### Step 2: Calculate the Distance Travelled in the First 5 Seconds
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