[填空题]
A hollow cylinder (hoorx: cq i 3j.e3a0yd)mvp) is rolling on a horizontal surface at speed v=3. i-.9w rs x f7 5r2iho0eceqxo q,uosb*v+x8d43 $m/s$ when it reaches a 15 $^{\circ} $ incline. (a) How far up the incline will it go? $\approx$ m (round to one decimal place) (b) How long will it be on the incline before it arrives back at the bottom? s