题目

如图，在Rt△ABC中，∠ACB=90º，AB=10，AC=6，点E、F分别是边AC、BC上的动点，过点E作ED⊥AB于点D，过点F作FG⊥AB于点G，DG的长始终为2．【小题1】当AD=3时，求DE的长；【小题2】当点E、F在边AC、BC上移动时，设，，求关于的函数解析式，并写出函数的定义域；【小题3】在点E、F移动过程中，△AED与△CEF能否相似，若能，求AD的长；若不能，请说明理由．阅读下列短文，选择方框中所给词的适当形式填空。 her, those, call, first, parent, uncle, on, take, key, eraser 1. Please __________ these things to your grandmother. 2. I found a set of ___________. Is it yours? 3. -- Can you ________ John at 555-7865?    -- OK. I know him. 4. -- Lucy, these are my _____________.    -- Nice to meet you! 5. – Excuse me, is __________ your ring in the lost and found case?    -- Yes, it is. Thank you. 6. -- What is your __________ name?    -- Frank. And my last name is Green. 7. Look at the girl under the tree. _________ is my cousin. 8. My father has two brothers. They are my ___________. 9. – What is this in English?    -- It is an ____________. 10. You can see some pictures _________ the wall. They are nice.