'4-2. A student on at ground moves a 16kg concrete block to the right at a' constant velocity as ShOWI'I in the diagram. The coefcient of friCtion between the block and the ground is 0.42. a) Draw a diagram showing the forces acting on the block in each case, and label the forces with appropriate symbols. b) If the student pushes the block, what is the pushing force applied by the student? c) If the student pulls the block, what is the pulling force applied by the student? d) In which case is less force required to move the block? EXplain the reason