Motion in one dimension 31 May

Q1-Following are two graphs between velocity and  height from the ground for a particle released from certain  height . After it strikes the ground , it bounces back only up to half of the height from where it was allowed to fall from the rest condition. Select the correct graph taking downward velocity as  negative.

2-A person is walking on a road at speed 2 m/s. Buses are plying on the same road with speed of 12 m/s in the same direction as the person. Every 40 second , the person is overtaken by a bus. What is the separation between two nearest buses?  

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