This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: Providing 25% of Namibia's revenue, mining is the single most important contributor to the economy. Namibia is the fourth largest exporter of non-fuel minerals in Africa and the world's fourth largest producer of uranium. There has been significant investment in uranium mining and Namibia is set to become the largest exporter of uranium by 2015. Rich alluvial diamond deposits make Namibia a primary source for gem-quality diamonds. While Namibia is known predominantly for its gem diamond and uranium deposits, a number of other minerals are extracted industrially such as lead, tungsten, gold, tin, fluorspar, manganese, marble, copper and zinc. There are offshore gas deposits in the Atlantic Ocean that are planned to be extracted in the future. According to "The Diamond Investigation", a book about the global diamond market, from 1978, De Beers, the largest diamond company, bought most of the Namibian diamonds, and would continue to do so, because "whatever government eventually comes to power they will need this revenue to survive".

Answer: How much revenue does mining provide Namibia?


Question: Spanish is currently the most widely taught non-English language in American secondary schools and of higher education. More than 1.4 million university students were enrolled in language courses in autumn of 2002 and Spanish is the most widely taught language in American colleges and universities with 53 percent of the total number of people enrolled, followed by French (14.4%), German (7.1%), Italian (4.5%), American Sign language (4.3%), Japanese (3.7%), and Chinese (2.4%) although the totals remain relatively small in relation to the total U.S population.

Answer: What language, other than English, is spoken in the U.S.?


Question: High-gain antennas have the advantage of longer range and better signal quality, but must be aimed carefully at the other antenna. An example of a high-gain antenna is a parabolic dish such as a satellite television antenna. Low-gain antennas have shorter range, but the orientation of the antenna is relatively unimportant. An example of a low-gain antenna is the whip antenna found on portable radios and cordless phones. Antenna gain should not be confused with amplifier gain, a separate parameter measuring the increase in signal power due to an amplifying device.

Answer:
Antennas with higher gain have what positive feature?