题目

阅读理解 A hospital has been forced to ban PokemonGo players from the site after a monster hub(妖怪枢纽站) was found in theA&E department. Royal Stoke University Hospital discovered that itscasualty unit(急诊室) is on the same spot as a Pokemon Go'gym' ­­ where players can train their newly caughtNintendo creatures. The University Hospitals ofNorth Midlands Trust agreed last week that patients can play Pokemon Go onwards because walking around is healthy. But the Trust has been forced to posta warning on its website about public access to A&E. It said if Pokemon Gobecomes足够长的粗糙斜面上，用力推着一物体沿斜面向上运动，t＝0时撤去推力，0～6 s内速度随时间的变化情况如图9所示，由图象可知(　　) A．0～1 s内重力的平均功率大小与1～6 s内重力平均功率大小之比为5∶1 B．0～1 s内摩擦力的平均功率大小与1～6 s内摩擦力平均功率大小之比为1∶1 C．0～1 s内位移大小与1～6 s内位移大小之比为1∶5 D．0～1 s内机械能变化量大小与1～6 s内机械能变化量大小之比为1∶5 图9