如图，抛物线y=x²+bx+c与直线y= $\frac{1}{2}$ x﹣3交于A、B两点，其中点A在y轴上，点B坐标为（﹣4，﹣5），点P为y轴左侧的抛物线上一动点，过点P作PC⊥x轴于点C，交AB于点D．

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Why do children like watching TV?

       Many children like watching TV. It's very interesting and they can see a lot and know many things about other people. They can learn from the radio, too. But they can learn easily from TV. Why? Because they can hear and watch at the same time. But they can't watch anything from the radio.

    TV helps to open children's mind. They can find better way to do things.

    Many children watch TV only on Saturday and Sunday evenings.They are very busy. But some children watch TV every night. They go to bed late. It's not good for their eyes and health.