[填空题]
A hollow cylinder (h. q7jq) yg6g n*y.qwb gmskp/m7/gd 4fox,vg ntjt1ia1: fs54u7 o8yvtop) is rolling on a horizontal 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