Ethan pushes a wooden box across a carpeted floor. then he pushes the same box across a smooth marble floor. why does ethan find it easier to push the box on the marble floor than on the carpeted floor? a. the box experiences more friction on the marble floor. b. the box experiences less friction on the marble floor. c. the box experiences more applied force on the marble floor. d. the box experiences less normal force on the marble floor.