In your physics lab, a block of mass m is at rest on a horizontal surface. You attach a light cord to the block and apply a horizontal force to the free end of the cord. You find that the block remains at rest until the tension T in the cord exceeds 20.0 N. For T > 20.0 N , you measure the acceleration of the block when T is maintained at a constant value, and you plot the results (Figure 1) . The equation for the straight line that best fits your data is a=[0.182m/(N⋅s2)]T−2.842m/s2.

PART A: For this block and surface, what is the coefficient of static friction.

PART B: For this block and surface, what is the coefficient of kinetic friction