1,Vy=gt=10*0.4=4m/stan53=Vy/Vo8/6=4/VoVo=3m/sV合=5m/s2,X=Vo*t=3*0.4=1.2mh=gt^2=10*0.16/2=0.9mD=1.5m (落地点到抛出点的直线距离=1.5m)