Problem: Hempstead, New York (CNN) -- President Barack Obama and Republican challenger Mitt Romney face off Tuesday in the second of their three debates, this one in a town hall-style setting in which they'll take questions from likely voters.

The stakes couldn't be higher: Obama must get his campaign back on track after a poor performance in the first debate that left Democrats demoralized and Obama's lead evaporating both in national polls and those in key battleground states. For Romney, who polls among voters showed won the first debate overwhelmingly, a second strong performance would boost his momentum going into the third debate next Monday and the final two weeks before Election Day.

Here are five things to watch for on Tuesday:

1. Connecting with the audience

Unlike the first presidential showdown in Denver two weeks ago, this debate will include a town hall audience of approximately 80 undecided voters, some of whom will get the chance to ask questions to the two candidates.

It's a completely different dynamic than the first face-off between the president and the Republican nominee.

"The challenge is that they've got to connect, not just with the people that are looking into the television and watching them, but to the people that are on the stage with them," the debate's moderator, CNN Chief Political Correspondent Candy Crowley, said.

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"They have to keep those folks in mind. It's a much more intimate and up close adventure with voters. The candidate that makes a connection with the person asking the question is also making a better connection with the person back at home," added Crowley, who's also the host of CNN's "State of the Union."
1. who is the debate's moderator?
2. who is she?
3. what else does she host?
4. is this the first debate?
5. then?
6. what kind of a setting will it be?
7. is the setting of the 2nd similar to the 1st?
8. who is in the debate?
9. what party is Romney?
10. who was better in the 1st?
11. how long before elections is the last one?
12. where was the first one?
13. how many people will be there for the 2nd?
14. what will the audience get to do?
15. how did the democrats feel after the 1st?
16. what day is this debate?
17. and what day is the third?
18. what is the challenge in this one?
19. do they connect just with the audience?
20. then who else?
Answer: 1. Candy Crowley
2. CNN Chief Political Correspondent
3. "State of the Union"
4. No
5. 2nd
6. Town hall
7. No
8. Barack Obama and Mitt Romney
9. Republican
10. Romney
11. Two weeks
12. Denver
13. About 80 undecided voters, other numbers unknown
14. Ask questions
15. Demoralized
16. Tuesday
17. Monday
18. To connect with voters
19. No
20. To the people watching on TV, and in person.

Problem: When NASA astronaut Scott Kelly completes his yearlong mission on the International Space Station next year, he'll come back just a little bit younger than his twin, Mark, than he was before. This is because time travels more slowly in space, a phenomenon first described by Albert Einstein's 1915 theory of general relativity.

This December, universities and academies around the world are celebrating the 100th anniversary of the theory's publication.

Even 60 years after his death, Einstein is still the most important scientist of the modern era. Looking back as far as 2,400 years ago, only Newton, Galileo and Aristotle were his equals.

Born in the era of horse-drawn carriages, his ideas started a technological revolution that brought about more change in one century than in the 2,000 years before.

In 1905, Einstein published four important scientific papers. These completely changed people's ideas about space, time, light and matter. In one of these papers Einstein. introduced his theory of special relativity. Two groundbreaking parts of the theory were about the relationship between mass and energy and the speed of light. Einstein was able to show that mass and energy were connected through the formula E=MC2. The theory also says that no object can travel faster than the speed of light.

About 10 years later came his theory of general relativity, the theory that modern physics is really based on. In Einstein's mathematics, space has three dimensions, and the fourth dimension is time. Space and time are part of one continuum, called space-time. The presence of mass changes space-time, which explains where gravity comes from.

Computers, satellites, telecommunication, lasers, television and nuclear power, many of the biggest developments in the modern world, can be linked to Einstein's work.

"We are a different people than we were a century ago," said astrophysicist Michael Shara of the American Museum of Natural. History, "completely different, because of Einstein."

However, there's more to him beyond the image of a science mastermind. Einstein, as a person, has also become a grandfatherly icon in our culture.

He liked playing Mozart on his Violin and keeping fit by hiking and walking. Power was not his goal. In 1952, the young nation of Israel asked Einstein to be its president, but he refused.

And, yes, he was eccentric. With hair like that, how could he not be?
1. Scott Kelly is what?
2. Does time travel more quickly in space?
3. What year did Einstein introduce the theory of relativity?
4. Even after death, Einstein is considered to be what?
5. Who were the only two people considered to be his equals?
6. He was born in the era of what?
7. His scientific papers completely changed people's ideas about what?
8. What formula did he come up with?
9. No object can travel faster than what?
10. Modern technology can be linked to what?
Answer: 1. an astronaut
2. no
3. 1915
4. the most important scientist the era
5. Newton, Gailieo and Aristotle
6. horse-drawn carriages
7. time, light and matter.
8. E=MC2
9. the speed of light.
10. Einstein's work.

Problem: Robert is sixteen now. He'll finish middle school in two years. His father has a shop and got much money. He hopes his son can go to university and makes him study hard. But the young man likes to play cards. He has to go out when his parents fall asleep. One night, when Robert came back, his father happened to see him. The old man was very angry and told his son to live upstairs. Robert has to go up and down quietly. Of course it troubles him. He thought and thought but didn't find a way. Last evening Robert listened carefully. And he was sure his parents went to sleep, he went out to play cards with his friends. He won some money and was happy. And he got back, he took off his shoes and was going upstairs. He heard a noise in his parents' bedroom. He stood behind the door and saw a man come out. He understood it was a thief . He stopped him at once. The man was very afraid and brought out all the things he stole in the room. "Tell me how you didn't wake my parents up," said Robert. "Or I'll take you to the police station!"
1. when will Robert finish middle school?
2. how old will he be?
3. what does his dad want him to do then?
4. what does he make Robert do?
5. What would he rather do?
6. when does he like to go out?
7. who caught him?
8. was he happy?
9. did he sneak out successfully after that?
10. did he go to play cards?
11. did he win?
12. what did he do before going up the stairs?
13. what made him pause?
14. What was it?
15. What was the intruder worried about?
16. What was Robert's concern?
17. what was he going to do if the intruder woke his parents?
Answer:
1. Yes
2. Eighteen
3. Go to university
4. Study hard.
5. Play cards
6. After his parents fall asleep
7. His father
8. No
9. Yes
10. Yes
11. Yes
12. Took off his shoes
13. He heard a noise
14. A thief
15. The things he stole
16. How the thief went up the stair without waking his parents.
17. ell me how you didn't wake my parents up," said Robert. "Or I'll take you to the police station