A 2.9 kg box starts from rest and slides down a plank of length d = 1.9 m that makes an angle of 290 with the horizontal as shown in the diagram. a. If the coefficient of friction between the box and the plank is 0.171 what is the nonconservative work done on the box? [3) b. What is the speed of the box when it reaches the bottom of the plank? (5} c. If the box slides even more on the flat surface at the base which has the same coefficient of friction. how far will it go before coming to rest? (3} d. How long will it take the box to come to rest after reaching the flat so rfa ce? (4} D