Problem: CEDAR RAPIDS, Iowa (CNN) -- Floodwaters inundated Iowa City and the University of Iowa arts campus on Sunday despite what one official called a "Herculean effort" to hold back the water with sandbags.

Residents surround Lt. Tobey Harrison at a Cedar Rapids checkpoint as they wait to see their homes Sunday.

"We've had the [National Guard] working next to prisoner inmates, sandbagging," said David Jackson, the university's facilities manager. "Students, faculty and staff, leaders of the university, the president of the university -- out sandbagging."

Some 500 to 600 homes were ordered to evacuate and others faced a voluntary evacuation order through the morning, said Iowa City Mayor Regenia Bailey.

The Iowa River in Iowa City crested at 31.5 feet and was expected to remain at that level until Monday, city and state officials said Sunday.

Classes at the university have been suspended until next Sunday, according to its Web site.

"All of our theaters, our music building, Clapp Recital Hall, our fine arts building [the] new Art Building West designed by Stephen Holl, has taken on significant water as well," said Sally Mason, president of the university. "Fortunately we were able to save all the art," she said.

The art was placed in crates shipped out of state last week.

"We anticipated the worst a week ago." At least 8 feet of water rushed through the campus, officials said. Among the school's 30,000 students, Ann Barber told CNN she has been sandbagging for nearly seven days.

"It's very hard to watch the devastation of our university," she said.
1. Who is the University's facility manager?
2. Which river crested at 31.5 feet?
3. Where is it located?
4. How deep was the water that rushed through the school?
5. How many stidents
6. She has been putting sand bags for days.
7. Were prisoners involved?
8. She is the city manager.
9. Who did a student talked to?
10. Pupils were able to save these.
11. They were put where?
Answer: 1. David Jackson
2. The Iowa River
3. Iowa City
4. 8 feet
5. 30,000
6. Ann Barber
7. yes
8. Regenia Bailey
9. CNN
10. all the art
11. in crates

Q: Theangelshavefinallybeenconnectedtogether andthebowshaveallbeencarefully fixed across the branches.After three months of hard work, 16-year-old Suzy Jordan's tree is finally appearing at the yearly Festival of Trees in honor of her best friend, Emily Austin.

"All that's needed now is a real angel,"says Suzy,"to help 13-year-old Emily recover from a recent bone marrow transplant and finally remove the leukemia "

"Emily is the strongest person I know.There's always such brightness about her,"says Suzy,a student ar Orem High School.

Last year,when Emily's cancer was _ ,she helped Suzy and other students decorate a red-and-white Christmas tree for Primary Children's Medical Center at the Festival of Trees.

"It was so much fun for her,"says Emily's mother, Laurie,"she's seen the inside of the hospital more than a school since she was 5".

But the good conditions didn't last long.In August, Suzy learned that her friend's leukemia returned, becoming worse.And she knew exactly what to do show her support.

"Emily was so excited about helping out with the festival tree last year that I decided to surprise her by giving away a tree of my own,"she says.

Because of being in hospital, Emily won't be able to see the tree."But I'm taking pictures to surprise her,"says Suzy."I want her to know that she'll always be an angel to me."

Suzy's tree has given Emily's family hope for a miracle ."It has given Emily hope that she has a chance to be a normal girl and do all the things other girls do,"says Laurie Austin.

Suzy's greatest hope is that she'll be able to give away more trees to the festival, with one big difference."The best wish of all,"she says,"is that Emily will be there with me, putting on the decoration."

Answer the following questions:
1. Who is Suzy's friend?
2. Does she have a problem?
3. Is it a health problem?
4. What is it?
5. What is the treatment?
6. How old is she?
7. How old is Suzy?
8. What kind of tree is she working on?
9. Where will it be shown?
10. Who is she trying to honor?
11. Did she get better?
12. When did the cancer return?
13. Where does Suzy go to school?
14. What did the tree do for Emily's family?
15. Will she be able to visit the tree in person?
16. Why not
17. How will she see it?
18. Who is taking them?
19. What color was the previous year's tree?
20. Did Emily help with it?
A: 1. Emily Austin.
2. yes
3. yes
4. leukemia
5. bone marrow transplant
6. 13
7. 16
8. Christmas tree
9. Primary Children's Medical Center
10. Emily
11. no
12. August
13. Orem High School
14. given them hope
15. no
16. she is in the hospital
17. pictures
18. Suzy
19. red and white
20. yes

Problem: Imagine what you could do with a machine that could make things disappear.

For inspiration, you could read some books. In the books of J.R.R. Tolkein, Bilbo Baggins finds a ring that can make him disappear. Of course, there's also poor Harry Potter, who used his invisibility cloak to hide from danger.

Now that you've got some ideas, it's time for the hard part: building the cloak. To do that, you have to give up science fiction and turn to real science. An invisibility cloak has to cheat anything or anyone who might be watching. In order to understand how something can be seen, it's important to understand how we see.

Human beings can only see objects that reflect light waves. These waves enter the eye and are then processed by the brain. However, if an object doesn't reflect light, then the waves don't enter the eye, and the brain doesn't process. So building an invisibility cloak is building something that doesn't reflect light.

Cummer was part of a team of scientists from Duke University, including David Smith and David Schurig, who built the world's first version of an invisibility cloak. They had been inspired by the work of a British physicist, John Pendry. He in May said that an invisibility cloak was possible and Pendry was not the only one thinking about a disappearing act. At the same time, a Scottish physicist, UIf Leonhardt published a paper on building invisibility equipment.

"It wasn't easy," says Cummer. "As often happens in science and research, it didn't work very well the first time. That first cloak didn't work like Harry Potter's --- the scientists didn't actually see anything disappear. So the research is still under way. "
1. what are people trying to build?
2. who tried to build the first one?
3. how many in the group?
4. were they named in the story?
5. what are the names of two of them?
6. who's work served as the inspiration for their project?
7. what novelist is mentioned?
8. what is the name of one of his characters?
9. what did he find?
10. did it do anything?
Answer:
1. an invisibility cloak
2. a team of scientists from Duke
3. Three
4. Yes
5. David Smith and David Schurig
6. Harry Potter
7. J.R.R. Tolkein
8. Bilbo Baggins
9. A ring
10. make him disappear