[填空题]
A hollow cylinder (hepl 45hm/:;psfld w+noop) is rolling on a horizontal surface atn: jtk; uup(c0 speed v=3.3 $m/s$ 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