Angular deceleration of wheels.

Right, so I have been stuck on this question for a while now but not sure where to start. I'm almost pulling my hair out, any guidance or pointers would be appreciated.

I need to calculate the** angular deceleration **of wheels of a lorry. It needs to stop in 0.5km using constant braking force.

It's weight is 5 tonnes and velocity is 80 km h-1. The wheels are 1.5m in diameter.

So far I've worked out the deceleration of the lorry (-0.494 ms-2), the braking force required (-2.4kN), the time taken to come to rest (2024.29), and the initial angular velocity of the wheels (29.63 rad/s).

Just can't get my head around the "angular deceleration" part. Can someone please tell me where to start.

Regards,

Becca.