A 1,120-N crate is being pushed across a level floor at a constant speed by a force F
of 310 N at an angle of 20.0° below the horizontal, as shown in the figure a below.

Two figures show a side view of a crate positioned upon a horizontal surface.
Figure (a): An arrow pointing downward and to the right is labeled vector F and forms an angle of 20° below the horizontal as it approaches the upper left edge of the crate.
Figure (b): An arrow pointing upward and to the right is labeled vector F and forms an angle of 20° above the horizontal as it extends from the upper right edge of the crate.
(a) What is the coefficient of kinetic friction between the crate and the floor? (Enter your answer to at least three decimal places.)

(b) If the 310-N force is instead pulling the block at an angle of 20.0° above the horizontal, as shown in the figure b, what will be the acceleration of the crate? Assume that the coefficient of friction is the same as that found in part (a).
m/s2