完形填空
I read a book about the secret of successful kids last week. In this book, we are told about 1 children who not only do well in their studies but also are 2 at sports, music, and so on.
One of the children in the book is John, a twelve-year-old boy. John works 3 at school and after school he does his homework and reviews what he has learned. John 4 a national science competition and won second prize. He is the captain of the school basketball team. And he takes piano or violin lessons every evening. He also 5 skiing on weekends.
John is happy though he is very 6 . He has a special notebook. In the notebook he writes his plans for the next few days. He 7 a smiling face beside each item(项目) that has been completed yet. He says that 8 you are well prepared you don't have to be worried.
John's parents always give him their support. They spend a lot of time with him, discussing things with him and giving him 9 . They also love to play with John. John says, "Whenever it's time to 10 , we forget all the work and just enjoy ourselves together!"
的交流电源上,副线圈所接的负载电阻是11Ω,则副线圈中电流大小是（ ）