3. A vehicle, which begins at rest at point \(P\), is travelling in a straight line.
For the first 4 seconds the vehicle moves with a constant acceleration of \(0.75 \mathrm {~m} \mathrm {~s} ^ { - 2 }\)
For the next 5 seconds the vehicle moves with a constant acceleration of \(- 1.2 \mathrm {~ms} ^ { - 2 }\)
The vehicle then immediately stops accelerating, and travels a further 33 m at constant speed.

1. Draw a velocity-time graph for this journey.
2. Find the distance of the car from \(P\) after 20 seconds.