Kinetic Energy and friction problem

[Zerobu]

Homework Statement

A 70kg base runner begins his slide into second base when he is moving at a speed of 4.0m/s. The co-efficient of friction between his clothes and the Earth is 0.70. He slides so that his speed is zero just before he reaches the base

(a). How much mechanical energy is lost due to friction acting on the runner?

(b) How far does he slide

Homework Equations

I think this has something to with the kinetic energy equation which 1/2mv^2

The Attempt at a Solution

I have no idea how to do this

 

[HallsofIvy]

You don't think that since they tell you that "The co-efficient of friction between his clothes and the Earth is 0.70." and that his mass is "70kg", the fact that there is 0.7(70)= 49 N force acting on his is at all relevant?