3. A car accelerates uniformly from rest to a speed of \(20 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) in \(T\) seconds. The car then travels at a constant speed of \(20 \mathrm {~m} \mathrm {~s} ^ { - 1 }\) for \(4 T\) seconds and finally decelerates uniformly to rest in a further 50 s .

1. Sketch a speed-time graph to show the motion of the car. The total distance travelled by the car is 1220 m . Find
2. the value of \(T\),
3. the initial acceleration of the car.