完形填空

   Nancy is reading an e-mail from her friend Jack. She is very1 to get the e-mail. Jack writes about his school2 his weekends. Jack likes his school very much. Nancy likes her school,3 . Jack's school is very big and he likes his classroom. The4  and chairs are new. There are lots of pictures5 the wall. They clean the classroom every day.

   Jack doesn't 6to school at the weekend. He gets up7at six on Saturday. He exercises in the park for half8. Then he eats his breakfast. He helps his mother do the9. At eight he begins to do his homework. He has lunch in a fast food restaurant (快餐店). In the10, he goes shopping with his mum. Sometimes he plays computer games or chats with his friends on the Internet. He enjoys his weekends very much.

将写有“p”字母的透明胶片放在显微镜下，观察到的物像是（  ）

某兴趣小组为了测定某未知碘片中碘化钾的含量，进行了如图实验：

（查阅资料知：碘化钾易溶于水，而碘化银是不溶于水的黄色沉淀）

在盒子中摸球，如果摸到一个黑球，那么(   )的说法是正确的。