Problem: Aircraft carrier:

Although STOVL aircraft are capable of taking off vertically from a spot on the deck, using the ramp and a running start is far more fuel efficient and permits a heavier launch weight. As catapults are unnecessary, carriers with this arrangement reduce weight, complexity, and space needed for complex steam or electromagnetic launching equipment, vertical landing aircraft also remove the need for arresting cables and related hardware. Russian, Chinese, and future Indian carriers include a ski-jump ramp for launching lightly loaded conventional fighter aircraft but recover using traditional carrier arresting cables and a tailhook on their aircraft.

What is a more fuel efficient way for STOVL aircraft to take off rather than vertically?
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A: using the ramp and a running start


Problem: Charleston, South Carolina:

The city also had a large class of free people of color. By 1860, 3,785 free people of color were in Charleston, nearly 18% of the city's black population, and 8% of the total population. Free people of color were far more likely to be of mixed racial background than slaves. Many were educated, practiced skilled crafts, and some even owned substantial property, including slaves. In 1790, they established the Brown Fellowship Society for mutual aid, initially as a burial society. It continued until 1945.

In what year did the Brown Fellowship Society end?
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A: 1945


Problem: Portugal:

A national railway system that extends throughout the country and into Spain, is supported and administered by Comboios de Portugal. Rail transport of passengers and goods is derived using the 2,791 km (1,734 mi) of railway lines currently in service, of which 1,430 km (889 mi) are electrified and about 900 km (559 mi) allow train speeds greater than 120 km/h (75 mph). The railway network is managed by the REFER while the transport of passengers and goods are the responsibility of Comboios de Portugal (CP), both public companies. In 2006 the CP carried 133 million passengers and 9,750,000 t (9,600,000 long tons; 10,700,000 short tons) of goods.

Into what country does Portugal's railway system expand?
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A: Spain


Problem: Copper:

Copper has been used since ancient times as a durable, corrosion resistant, and weatherproof architectural material. Roofs, flashings, rain gutters, downspouts, domes, spires, vaults, and doors have been made from copper for hundreds or thousands of years. Copper's architectural use has been expanded in modern times to include interior and exterior wall cladding, building expansion joints, radio frequency shielding, and antimicrobial indoor products, such as attractive handrails, bathroom fixtures, and counter tops. Some of copper's other important benefits as an architectural material include its low thermal movement, light weight, lightning protection, and its recyclability.

How long has copper been used in building construction?
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A:
hundreds or thousands of years