This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

Q: Passage: The tradition holds that Virgil was born in the village of Andes, near Mantua in Cisalpine Gaul. Analysis of his name has led to beliefs that he descended from earlier Roman colonists. Modern speculation ultimately is not supported by narrative evidence either from his own writings or his later biographers. Macrobius says that Virgil's father was of a humble background; however, scholars generally believe that Virgil was from an equestrian landowning family which could afford to give him an education. He attended schools in Cremona, Mediolanum, Rome and Naples. After considering briefly a career in rhetoric and law, the young Virgil turned his talents to poetry. Question: In which cities did Virgil attend schools?

A: Cremona, Mediolanum, Rome and Naples
****
Q: Passage: Shell sold 9.5% of its 23.1% stake in Woodside Petroleum in June 2014 and advised that it had reached an agreement for Woodside to buy back 9.5% of its shares at a later stage. Shell became a major shareholder in Woodside after a 2001 takeover attempt was blocked by then federal Treasurer Peter Costello and the corporation has been open about its intention to sell its stake in Woodside as part of its target to shed assets. At a general body meeting, held on 1 August 2014, 72 percent of shareholders voted to approve the buy-back, short of the 75 percent vote that was required for approval. A statement from Shell read: "Royal Dutch Shell acknowledges the outcome of Woodside Petroleum Limited's shareholders' negative vote on the selective buy-back proposal. Shell is reviewing its options in relation to its remaining 13.6 percent holding." Question: What percentage of shareholder votes was need to approve the 2014 buy-back?

A: 75
****
Q: Passage: Solar energy may be used in a water stabilisation pond to treat waste water without chemicals or electricity. A further environmental advantage is that algae grow in such ponds and consume carbon dioxide in photosynthesis, although algae may produce toxic chemicals that make the water unusable. Question: What is a reason why the water from a water stabilisation pond may be unusable?

A:
algae may produce toxic chemicals
****