阅读材料回答问题

材料一：广东省委、省政府出台《关于进一步促进粤东西北地区振兴发展的决定》，强调广东不仅需要把珠三角地区这一个增长极继续做优做强，还需要把粤东西北地区培育成新的增长极，共同支撑我省经济长远发展。要将粤东西北地区打造成与珠三角并列的经济发动机，巩固广东的华南地区区域经济中心地位，是广东的发展继续走在全国前列。

材料二：中央经济工作会议指出，着力做好保障和改善民生工作。要继续按照守住底线、突出重点、完善制度、引导舆论的思路，统筹教育、就业、收入分配、社会保障、医药卫生、住房、食品安全、安全生产等，切实做好改善民生各项工作。

在光滑水平面上，质量为m的小球A正以速度v₀匀速运动．某时刻小球A与质量为3m的静止小球B发生正碰，两球相碰后，A球的动能恰好变为原来的 $\frac{1}{4}$ ．则碰后B球的速度大小是（   ）

    2014 is the year of horse in China. Do you know anything about the horse?

    The horse is strong and runs very fast. He's a useful and hard-working animal. The horse learns to know his owner soon. He loves his owner, even after his owner loses his life. Here's a story about such a horse. In a war, the owner passed away(死), and fell from his horse. When people found his body some days later, the horse was still standing beside it. During that long time, the horse didn't leave the body of his owner, without food or water, in the coldest weather, driving away the birds that might eat it. Wasn't he a great animal?