\fQuestion 18 3 Points Suppose the coefficient of static friction of a horizontal surface is 0.388 and the coefficient of kinetic friction of the surface is 0.360. Block A of mass 30.0kg rests on a horizontal surface (Fig. 2.1), (a) what is the magnitude and direction of the frictional force on the block? If an attached string is parallel to the surface and passes over an ideal pulley, as shown in Fig. 2.2. Block B of mass 3.00 kg is attached to the dangling end of the string, (b) what is the magnitude and direction of the frictional force on block A if it rests on the horizontal surface? If the mass of block B can be changed, (c) what is the mass of block B so that block A is at the verge of motion? If the mass of block B is increased to 16.0 kg (Fig. 2.3), (d) what is the magnitude and direction of the frictional force on block A, (e) what is the magnitude of acceleration of block A, and (f) what is the tension on the string