先化单位:底面半径0.25m,高0.5m.则底面积和顶面积为:0.25^2×π=0.3925m^2
侧面积:2×π×0.25×0.5=0.785m^2 总面积:1.1775m^2
所以需要油漆:1.1775×1000×0.7=824.25kg