B. A car moving at an initial speed vi applies its brakes and skids for some distance until coming to a complete stop. If the coefficient of kinetic friction between tires and the road is µk what distance did the car skid?

Complete Question

The complete question is  shown on the first uploaded image  

The distance which the car skid is  

Explanation:

From the question we are told that  

     The  initial velocity of the car is  

     The  coefficient of kinetic friction is  

According to the law of energy conservation

    The initial Mechanical Energy =  The final  Mechanical Energy  

The initial mechanical energy is  mathematically represented as  

where KE is the initial kinetic energy which is  mathematically represented as

And  PE  is  the initial potential energy which is  zero given that the car is  on the ground

     Now  

Where   is  the work which friction exerted on the car  which is  mathematically represented as

Where   is the distance covered by the car before it slowed down

=>    

the answer should be in the picture.