Finding the coefficient of static friction in a centripiton force equation

[nikni]

Homework Statement

a bus passanger has her laptop sitting on the seat next to her while the bus moves at 10m/s, the bus goes around a turn with a radius of 25m. what is the coefficient of static friction in order to keep the laptop from sliding?

Homework Equations

The Attempt at a Solution

ff=πfn
ac=v^2 /r
cant figure out the correct formula of formulas to use

 

[vela]

It's a force problem, so ∑F=ma is a good one to consider using.

As with all force problems, start by drawing a free-body diagram.