[b]1. A van is traveling at 80 km/h at 25 m/s undergoes uniform deceleration when the brakes are applied, slowing to 50 km/h at 10 m/s after 2.1 s. (a) what is the deceleration? (b) How far does it travel during this period? (c) How much farther does it travel before stopping if deceleration remains constant?

Variables= i dont understand what is meant by 80km/h at 25m/s and 50km/h at 10m/s

vi=25m/s? vf=10m/s? t=2.1s 1)find=-a? 2)displacement=? 3)at vf=0 displacement?

**2. Relevant equations**

1)i used d=(vi+v2)/2 x t

2)vf=vi+at to find acceleration

3)know how to compute but didnt because im unsure of my answer what to do with 80km/h what does this mean??? please help

**3. The attempt at a solution**

d=37m

a=-7.14m/s^2

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