问题
完形填空
| 完形填空。 | ||||
| The family had just moved. The young woman was feeling a little 1 . It was Mother's Day - and she was 800 miles away from her parents. She had called them that morning, and her mother had 2 how colorful their backyard was 3 spring had arrived. Later, she told her husband how she 4 those lilacs (丁香) in her parents' yard. "I know where we can find some," he said. "Get the 5 and come on." So off they went. Some time later, they stopped at a hill and there were lilacs all round. The young woman rushed up to the nearest 6 and buried her face in the flowers. Carefully, she 7 some. Finally, they returned to their car for the 8 home. The woman sat smiling, surrounded by her 9 . When they were near home, she shouted "Stop," got off quickly and 10 to a nearby nursing home. She went to the end of the porch (门廊), where a(n) 11 patient was sitting in her wheelchair, and put the flowers into her lap. The two 12 , breaking into laughter now and then. Later the young woman turned and ran back to her 13 . As the car pulled away, the woman in the wheelchai r 14 with a smile, and held the lilacs 15 . "Mom," the kids asked, " 16 did you give her our flowers?" "It is Mother's Day, and she seems so 17 while I have all of you. And anyone would be 18 by flowers." This pleased the kids, but not the husband. The next day he 19 some young lilacs around their yard. I was the husband. Now, every May, our yard is full of lilacs. Every Mother's Day our kids 20 purple lilacs. And every year I remember that smile of the lonely old woman. And that has become a forever touching memory of my life. | ||||
|
答案
1-5: DCAAB 6-10: ABCCD 11-15: BDABD 16-20: ACDCB
）发生核反应，生成氚核（
）和α粒子，同时释放出
的核能（
）。 
的动能和锂核发生正碰，且碰撞前中子和锂核具有等大反向的动量，核反应过程中释放出的核能全部转化为动能，则反应后生成的氚核和α粒子的动能各为多大？