In this task, you're given an article and an answer. Your task is to generate the question for the answer based on the given article.
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Question: Article: My 11-year-old son and I rides bikes to and from his school every day. I accompany him on the 20-minute ride through Manhattan, drop him off and return at the end of day to pick him up. We always ride together; sometimes he leads; sometimes I do. And as we ride, we communicate the ways to minimize the dangers: Don't go too fast, and watch out for doors suddenly swinging out from parked cars and jaywalking pedestrians, etc. Some friends worry about the risk of riding in traffic, but is there a better way to let my son know how to deal with traffic dangers? But recently he requested me to start hanging back a half block or so. This way he could enjoy the feeling of riding on his own, with the security of knowing that I was nearby in case he needed me. This is healthy, of course, as my son needs space to develop independence in preparation for his inevitable (,) departure from home. However, that means soon he will want to ride to school on his own, and I will no longer have this wonderful routine. "Let your children go if you want to keep them." I understand this and am trying to let my son go in age-appropriate phases, but I still suffer. It's one of the most troubling experiences of parenthood -- recognizing that your presence is becoming less welcome. My dilemma as a husband mirrors the concern I feel as a parent. My wife has just left on a six-month mission to cover the situation in Libya. In the days leading up to her departure, we spoke openly about the possibility, however unlikely, that she might be killed. But while I influence her decisions, I do not control them. Finally, it was her decision. I know that letting go is the wisest path in this case too. As we travel through life's phases, we must let go of so much. And I don't think it gets easier with practice. But maybe just accepting that eventually we will have to let go is the secret to living a full life.
Answer: To teach his son to ride in traffic.

Answer: Why does the writer accompany his son on his daily ride to school?

Question: Article: NANJING -- Another human H7N9 case has been found in east China's Jiangsu Province, the provincial health department confirmed on January 31. The patient, a 75-year-old woman from the provincial capital of Nanjing, is in a critical condition. The case brings the number of infections in the province to eight this year. H7N9 has killed 19 in China this year, and the total number of human infections reached 96 on January 26, according to the Chinese Center for Disease Control and Prevention. With bird flu cases increasing on a daily basis, public concern over people-to-people transmission during Spring Festival is growing. Li Lanjuan, researcher at the Chinese Academy of Engineering and a specialist in H7N9 prevention, said so far there have not been any cases in which one person transmits the flu to another, and the latter transmits the virus to a third person. Her team has identified H7N9 virus mutations this year, but the _ are not large-scale. "Inter-human transmission is very unlikely," said Li, who added that the virus has not evolved to be extensively drug resistant. The National Health and Family Planning Commission said on Wednesday live poultry markets should close if any case of H7N9 avian flu is detected. The southern metropolis of Shenzhen has closed all live poultry markets until February 13 for a thorough cleaning. The city near Hong Kong has reported 14 human H7N9 cases since December 18. Live poultry trading has been halted in Hangzhou, Ningbo and Jinhua cities in Zhejiang, which reported the largest number of human H7N9 cases. China has stepped up research for an H7N9 vaccine in the face of the increasing threat from the virus. Beijing's Snovac Hotech Ltd.,which developed the A/H1N1 and H5N1 vaccines, said in a press release on Wednesday that it has completed preclinical studies of an H7N9 vaccine arid prepared several types for clinical testing. The company has submitted an application to the China Food and Drug Administration to start clinical trials.
Answer: It once developed the A/H1N1 and H5N1 vaccines.

Answer: Which of the following is true about Beijing's Sinovac Biotech Ltd?

Question: Article: On July 1 at exactly 7:59:59, Bejing time, the world' s atomic clocks will pause for a single second, or, more precisely, change to the unusual time of 7:59:60. The addition of a leap second , is to keep our clocks in time with the slowing of Earth' s rotation and astronomical time as measured by the sun. Just one extra second could affect the way computers and websites work, however. When the last leap second was added back in 2012, the community website Reddit crashed. For Reddit, the problem was that a Linux system got confused when it checked the network time and found an extra second. Speaking to Wired about the problem back in 2012, Linux creator Linus Torvalds commented:"Almost every time we have a leap second, we find something. It' s really annoying, because it' s code that is almost never used, and thus not tested by users under their normal conditions. " Companies have thought of their own solutions, and Google' s"leap smear"may be the best- known example. As company engineer Christopher Pascoe explains in a blog post, companies usually try to turn back the clocks by one second at the end of the day so that they play that second again. However, Pascoe believes this creates problems. He asked:"Does email that comes in during that second get stored correctly?"Google has a solution: Cut the extra second into milliseconds and then put these tiny amounts of time into the system throughout the day."This means that when it became time to add an extra second at midnight."Says Pascoe."Our clocks have already taken this into account over the course of the day." For many companies without Google' s money, however, the leap second will likely still cause some crashes.
Answer: To record the changes to astronomical time.

Answer:
Why do we need to add a leap second?