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: Metro Pocket Guide Metrorail  Each passenger needs a farecard to enter and go out. Up to two children under ago five may travel free with a paying customer. Farecard machine are in every station, Bring small bills because there are no change machines in the station and farecard machine only provide up to $ 5 in change. Get one of unlimited Metrorail rides with a One Day Pass. Buy it from a farecard machine in Metro stations. Use it after 9:30 a. m. until closing on weekdays, and all day on weekends and holidays. Hours of Service Open: 5 a. m Mon-Fri           7a. m. Sat--Sun . Close: midnight Sun--Thurs     3 a.m. Fri.---Sat. nights. Last train times vary. To avoid missing the last train, please check the last train times posted in the station. Metrobus When paying with exact change, the fare is $ 1. 35 . when paying with a smarTrip card, the fare is $1. 25 Fares for the Senior /disabled customers Senior citizens 65 and older and disabled customers may ride for half the regular fare. On Metrorail and Metrobus, use a senior/disabled farecard or SmarTrip card. For more information about buying senior/disabled farecards, farecard or SmarTrip cards and passes, please visit MetroOpenDoors. com or call 202-637-7000 and 202-637-8000. Senior citizens and disabled customers can get free guide on how to use proper Metrobus and Metrorail services by calling 202-962-1100 Travel tips   . Avoid riding during weekday rush periods -before 9:30 a. m. and between 4 and 6 p. m. . If you lose something on a bus or train or in a station, please call Lost & Found at 202-962-1195. 
 Answer: They make change for no more than $5.

Answer: What should you know about farecard machine?


Question: Article: Like many new graduates, I left university full of hope for the future but with no real idea of what I wanted to do. My degree, with honors, in English literature had not really prepared me for anything practical. I knew I wanted to make a difference in the world somehow, but I had no idea how to do that. That's when I learned about the Lighthouse Project. I started my journey as a Lighthouse Project volunteer by reading as much as I could about the experiences of previous volunteers. I knew it would be a lot of hard work, and that I would be away from my family and friends for a very long time. In short, I did not take my decision to apply for the Lighthouse Project lightly. Neither did my family. Eventually, however, I won the support of my family, and I sent in all the paperwork needed for the application. After countless interviews and presentations, I managed to stand out among the candidates and survive the test alone. Several months later, I finally received a call asking me to report for the duty. I would be going to a small village near Abuja, Nigeria. Where? What? Nigeria? I had no idea. But I was about to find out. After completing my training, I was sent to the village that was small and desperately in need of proper accommodation. Though the local villagers were poor, they offered their homes, hearts, and food as if I were their own family. I was asked to lead a small team of local people in building a new schoolhouse. For the next year or so, I taught in that same schoolhouse. But I sometimes think I learned more from my students than they did from me. Sometime during that period, I realized that all those things that had seemed so strange or unusual to me no longer did, though I did not get anywhere with the local language, and returned to the United States a different man. The Lighthouse Project had changed my life forever. 
 Answer: His university education focused on the theoretical knowledge.

Answer: What do we know about the author?


Question: Article: Scientists from the University of East Anglia have identified four new man-made gases that are contributing to the damage to the ozone  layer. Two of the gases are accumulating at a rate that is causing concern among researchers.      Worries over the growing ozone hole have seen the production of chlorofluorocarbon (CFC) gases restricted since the mid 1980s. But the precise origin of these new, similar substances remains a mystery.      Lying in the atmosphere, the ozone layer plays a critical role in blocking harmful UV rays, which cause cancers in humans and reproductive problems in animals.       Scientists from the British Antarctic Survey were the first to discover a huge "hole" in the ozone over Antarctica in 1985. The evidence quickly pointed to CFC gases, which were invented in the 1920s, and were widely used in refrigeration. Extraordinarily, global action was rapidly agreed to deal with CFCs and the Montreal Protocol to limit these substances came into being in 1987. A total global ban on production came into force in 2010.      Now, the newly discovered four new gases can destroy ozone and are getting into the atmosphere from as yet unidentified sources. Three of the gases are CFCs and one is a hydrochlorofluorocarbon (HCFC), which can also damage ozone.      The research has shown that four gases were not around in the atmosphere at all until the 1960s, which suggests they are man-made. The scientists discovered the gases by analyzing polar snow pack. Air from this snow is a natural archive of what was in the atmosphere up t0 100 years ago. The researchers also looked at modern air samples, collected at remote Cape Grim in Tasmania.      They estimate that about 74,000 tonnes of these gases have been released into the atmosphere. Two of the gases are accumulating at significant rates. However, they don't know where the new gases are being released from and this should be investigated. Possible sources include chemicals  for insecticide  production and solvents   for cleaning electronic components. The three CFCs are being destroyed very slowly in the atmosphere - so even if emissions  were to stop immediately, they will still be around for many decades to come.      Of the four species identified, CFC-113a seems the most worrying as there is a very small but growing emission source somewhere, maybe from agricultural insecticides. We should find it and take it out of production. 
 Answer: The CFCs will have a long impact once they are released.

Answer:
What do we know about the newly discovered gases?


