Calculate the force applied and constant frictional force opposing its motion

[MsHomework]

A 0.50kg skateboard is at rest on a rough, level floor on which two lines have been drawn 1.0m apart. A constant horizontal force is applied to the shateboard at the beginning of the interval, and is removed at the end. The skateboard takes 8.5s to travel the 1.0m distance, and it then coasts for another 1.25m before coming to rest. calculate the force applied to the skateboard, and also the constant frictional force opposing its motion.

 

[Zula110100100]

What equations come into play here and what is your attempt at a solution?

 

[MsHomework]

Well I was thinking of the the Newton's second law, which is F(net)=m*a. Then I need acceleration. Which is confusing because both the velocities are at rest since it starts from a rest and ends at a rest. So I really don't know what to do!