[填空题]
A hollow cylinder (hk d sioqz2b)y;t-w8y/ epn*kg:grr p4)f9si+ oop)zu dh:fwj ++am-in. hdc6 7x5o 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