题目

阅读短文，掌握大意，然后从A、B、C、D四个选项中，选出可以填入空白处的最佳选项。 A little sports shop is near my house. It sells (卖) many good things for 1 . At the shop, we can buy soccer balls, 2 , basketballs and so on. Today my 3 and I go to the4 to buy a tennis racket. There are a lot of 5 . And they have different 6. I think every racket 7 very nice. My sister chooses (选择) a black one, because black is her favorite8 . You know, my sister is a big sports fan. She has a great sports 9at home-five soccer balls, four basketballs and many tenni（题文）如图所示，一个闭合三角形导线框ABC位于竖直平面内，其下方略靠前固定一根与线框平面平行的水平直导线，导线中通以图示方向的恒定电流释放线框，它由实线位置下落到虚线位置未发生转动，在此过程中（ ）A. 线框中感应电流方向依次为顺时针逆时针B. 线框的磁通量为零时，感应电流却不为零C. 线框所受安培力的合力方向依次为向上向下向上D. 线框所受安培力的合力为零，做自由落体运动