A 100-Kg Box Is Placed on a Ramp $\degree$ What Is the Coefficient of Static Friction Between Box

A 100-kg box is placed on a ramp. As one end of the ramp is raised, the box begins to move downward just as the angle of inclination reaches 25 $\degree$ . What is the coefficient of static friction between box and ramp?

A) 0.15
B) 0.27
C) 0.47
D) 0.95