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    Both of my parents worked full-time when I was a little girl, so my grandmother would stay at our house during the day. We would watch game shows in the living room. Our favorite was The Price is Right. We would call out our answers along with the contestants.

    When I got older and started going to school, we couldn't watch our game shows regularly. That was okay with me, though, because the one thing I liked better than watching game shows with my grandmother was helping her bake. Watching her in the kitchen was amazing: she never seemed to need the recipes but everything she made tasted delicious.

    At first I would just sit in the kitchen and watch, even though I didn't understand what she was doing. As I got older, she let me help with the easy parts, such as measuring the sugar. The day she let me separate the eggs，I felt like I had found complete pleasure.

    At last, my parents decided that I could take care of myself，and my grandmother stopped coming over every day. The love of baking, however, stayed with me. I started baking by myself, and even if the cookies ended up burnt sometimes, more often they turned out pretty well. I tried out new recipes, and whenever I got to a thorny part, I would call my grandmother for advice. Sometimes I would call her just to talk, too. I felt like I could talk to her about anything.

    My grandmother passed away ten years ago, but I still think of her every day. Last week, I found a recipe book she made for me. It included her recipes for brownies, cookies, and my favorite, lemon pie. As I looked through the pages, I thought I could hear her voice. She was the one who taught me not just about baking, but about life.

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在电场中的某点A放一个检验电荷，其电荷量为q，受到的电场力为F，则A点的电场强度为E= $\frac{F}{q}$ ，下列说法正确的是（   ）