A particle of mass 2 kg is initially at rest on a rough horizontal plane. A force of magnitude 10 N is applied to the particle at 15° above the horizontal. It is given that 10 s after the force is applied, the particle has a speed of 3.5 m s^-1.

(i) Show that the magnitude of the frictional force is 8.96 N, correct to 3 significant figures.

(ii) Find the coefficient of friction between the particle and the plane.