Are these even possible? (Friction Related)

[bassboy]

Homework Statement

An object rests on an inclined plane. One end of the plane is lifted until the object begins to slide. The angle at which the object begins to slide is 35 degrees. What is the Coefficient of Friction

Homework Equations

f_k = µ_kF_n
f_s^max=µ_sF_n

The Attempt at a Solution

Honestly, I don't even know where to begin on this one. Only one variable is given, in what looks (to me) to be a problem where more than one variable is called for to be solved.
Similarly...

Homework Statement

Nike uses a sole for a line of shoes that has a coefficient of friction, µ=.3. Find the maximum acceleration that a runner using these shoes can have.

 

[tiny-tim]

Welcome to PF!

An object rests on an inclined plane. One end of the plane is lifted until the object begins to slide. The angle at which the object begins to slide is 35 degrees. What is the Coefficient of Friction

Hi bassboy! Welcome to PF!

Hint: What is the normal force, F_n, when the angle is 35º?

Nike uses a sole for a line of shoes that has a coefficient of friction, µ=.3. Find the maximum acceleration that a runner using these shoes can have.

Show us what you've tried, and where you're stuck, and then we'll know how to help.