Suppose that two workers simultaneously push on a 75.0kg crate with forces Fa(450.N, at an angle of 20.0 degrees from the crate) and Fb(580.N at an angle of 40.0 degrees from the crate). Assume that both of these forces remain constant as the crate moves. The floor is exactly horizontal.

a. If the crate starts out with zero friction between with crate and the floor, find the magnitude and direction of the resulting accerleration of the crate.

b. Find the magnitude of the normal force from the floor.

c. Suppose the crate is already in motion when it encounters a patch of floor where kinetic friction is present. The crate now slides at a constant speed. Find the coefficient of kinetic friction.