The block shown is observed to have a velocity v1 = 21 ft/sec as it passes point A and a velocity v2 = 12 ft/sec as it passes point B on the incline. Calculate the coefficient of kinetic friction µk...

The block shown is observed to have a velocity v₁ = 21 ft/sec as it passes point A and a velocity v₂ = 12 ft/sec as it passes point B on the incline. Calculate the coefficient of kinetic friction µ_k between the block and the incline if x = 34 ft and θ = 20°. Use acceleration due to gravity of 32.2 ft/s².