简述表面活性剂的性能。
（）是库存原材料资金的平均占用额与最高占用额的比例。
Once there was a little girl who came to live in an orphanage (孤儿院). As Christmas time was drawing near, all of the other children 11 telling the little girl about the beautiful Christmas tree that would appear in the hall downstairs on Christmas morning. After their usual 12 , each child would be given their only Christmas gift, a small orange.
The headmaster of the orphanage was very 13 with the kids. So on Christmas Eve, when he 14 the little girl slipping down the stairs to peek（偷看）at the much-heard-of Christmas tree, he 15 that the little girl would not receive her Christmas orange because she had been so curious as to disobey the rules. The little girl ran back to her room 16 , crying at her terrible fate. The next morning as the other children were going down for breakfast, the little girl stayed in her bed. She couldn’t 17 the thought of seeing the others receive their gift while there would be 18 for her. Later, as the children came back upstairs, the little girl was surprised to be handed a napkin (餐巾). As she carefully opened it, there, to her 19 , was an orange all peeled and sectioned (分瓣). “ How could this be? ” she asked. Then, she realized how each child had taken one section from their orange for her so that she, too , would have a Christmas orange. What an example of the true meaning of Christmas those orphan children showed that morning! How I 20 the world would show the same kind of concern for others, not only at Christmas, but throughout the year!
请在17处填上正确答案（） ["stand","understand","remember","find"]
什么是放火毁林罪？犯该罪要受何处罚？
教育学是研究人类（），揭示（）的一门科学。
张季鸳
