[填空题]
A hollow cylinder (hoop) is rolling on a ehz,m-0ga2 tri 2/xnyhorizontalmr/h*u ,y.p 7rw bsinl xgu;h,doq u3z8o 4*.y surface at 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