[填空题]
A hollow cylinder (hoop) is rolling on a horizontaly1(myi k+vr w1qak((kzgo3ez2 /et8 u surface at speed v=3.3d1 mpy kk1*gt2 $m/s$ 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