Extract the answer to the question from the following context. Question: Originally in Washington, D.C. and Manhattan, what system of powering streetcars was more popular? Context: Some street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. "plow") accessed through a narrow slot in the road. In the United States, much (though not all) of the former streetcar system in Washington, D.C. (discontinued in 1962) was operated in this manner to avoid the unsightly wires and poles associated with electric traction. The same was true with Manhattan's former streetcar system. The evidence of this mode of running can still be seen on the track down the slope on the northern access to the abandoned Kingsway Tramway Subway in central London, United Kingdom, where the slot between the running rails is clearly visible, and on P and Q Streets west of Wisconsin Avenue in the Georgetown neighborhood of Washington DC, where the abandoned tracks have not been paved over. The slot can easily be confused with the similar looking slot for cable trams/cars (in some cases, the conduit slot was originally a cable slot). The disadvantage of conduit collection included much higher initial installation costs, higher maintenance costs, and problems with leaves and snow getting in the slot. For this reason, in Washington, D.C. cars on some lines converted to overhead wire on leaving the city center, a worker in a "plough pit" disconnecting the plough while another raised the trolley pole (hitherto hooked down to the roof) to the overhead wire. In New York City for the same reasons of cost and operating efficiency outside of Manhattan overhead wire was used. A similar system of changeover from conduit to overhead wire was also used on the London tramways, notably on the southern side; a typical changeover point was at Norwood, where the conduit snaked sideways from between the running rails, to provide a park for detached shoes or ploughs.
Ans: conduit third-rail

Extract the answer to the question from the following context. Question: What is the difference in the ability to take in raw materials? Context: Regardless of the type of metabolic process they employ, the majority of bacteria are able to take in raw materials only in the form of relatively small molecules, which enter the cell by diffusion or through molecular channels in cell membranes. The Planctomycetes are the exception (as they are in possessing membranes around their nuclear material). It has recently been shown that Gemmata obscuriglobus is able to take in large molecules via a process that in some ways resembles endocytosis, the process used by eukaryotic cells to engulf external items.
Ans: The Planctomycetes are the exception (as they are in possessing membranes around their nuclear material)

Extract the answer to the question from the following context. Question: What island did the Spaniards trade with inhabitants on? Context: The Spanish ship San Pedro and two other vessels in an expedition commanded by Miguel Lopez de Legazpi discovered an island on January 9, 1530, possibly Mejit, at 10N, which they named "Los Barbudos". The Spaniards went ashore and traded with the local inhabitants. On January 10, the Spaniards sighted another island that they named "Placeres", perhaps Ailuk; ten leagues away, they sighted another island that they called "Pajares" (perhaps Jemo). On January 12, they sighted another island at 10N that they called "Corrales" (possibly Wotho). On January 15, the Spaniards sighted another low island, perhaps Ujelang, at 10N, where they described the people on "Barbudos". After that, ships including the San Jeronimo, Los Reyes and Todos los Santos also visited the islands in different years.
Ans: Los Barbudos

Extract the answer to the question from the following context. Question: Why does it seem odd that the ships are retiring? Context: The Royal Navy is constructing two new larger STOVL aircraft carriers, the Queen Elizabeth class, to replace the three now retired Invincible-class carriers. The ships are HMS Queen Elizabeth and HMS Prince of Wales. They will be able to operate up to 40 aircraft on peace time operations with a tailored group of up to 50, and will have a displacement of 70,600 tonnes. HMS Queen Elizabeth is projected to commission in 2017 followed by Prince of Wales in about 2020. The ships are due to become operational starting in 2020. Their primary aircraft complement will be made up of F-35B Lightning IIs, and their ship's company will number around 680 with the total complement rising to about 1600 when the air group is embarked. The two ships will be the largest warships ever built for the Royal Navy.
Ans: Invincible