如图所示，匀强磁场垂直于圆形线圈指向纸里，a、b、c、d为圆形线圈上等距离的四点，现用外力作用在上述四点，将线圈拉成正方形，设线圈导线不可伸长，且线圈仍处于原先所在的平面内，则在线圈发生形变的过程中
A．线圈中将产生abcd方向的感应电流
B．线圈中将产生adcb方向的感应电流
C．线圈中产生感应电流的方向先是abcd，后是adcb
D．线圈中无感应电流产生
答案：A
One of the most difficult things for children to deal with when moving to a new town is leaving their friends and making new ones. We once moved and one of our new neighbors told us about a summer camp at the Recreation Center all the kids went to. My husband and I looked into it and we found it was unbelievably cheap. I had the kids sign up (报名) the next day so that they could know more kids there. Another thing we did was to have them sign up for sports when school started. They were happy to be on teams with new friends they made. This also gave me a chance to meet new people and from them I sometimes got some useful ideas for my new books. If you’re just moving to a new house in the same city you live in now, it won’t really be a problem unless your kids are changing schools. If they are, it is a great idea to have them take the address book to school. Thus, your children won’t feel “lost” without their old friends. If you’re able to, over the summer vacation, try inviting the friend your child misses most to come and visit your new home for a week, or even a few weeks. I know this can be difficult if that child has to fly, but maybe you can work out a plan with the child’s parents. Think how happy the kids will be when they meet! 小题1:  The author had her kids sign up for the summer camp mainly because _____.
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her kids a chance to meet more kids