A 5.00 -kg block is set into motion up an inclined plane with an initial speed of $8.00 \mathrm{m} / \mathrm{s}$ (Fig. $\mathrm{P} 7.25$ ). The block comes to rest after traveling $3.00 \mathrm{m}$ along the plane, which is inclined at an angle of $30.0^{\circ}$ to the horizontal. For this motion, determine (a) the change in the block's kinetic energy, (b) the change in the potential energy of the block-Earth system, and (c) the friction force exerted on the block (assumed to be constant). (d) What is the coefficient of kinetic friction?