Extract the answer to the question from the following context. Question: What fails to prevent evaporation in the bulb? Context: On 13 December 1904, Hungarian Sándor Just and Croatian Franjo Hanaman were granted a Hungarian patent (No. 34541) for a tungsten filament lamp that lasted longer and gave brighter light than the carbon filament. Tungsten filament lamps were first marketed by the Hungarian company Tungsram in 1904. This type is often called Tungsram-bulbs in many European countries. Filling a bulb with an inert gas such as argon or nitrogen retards the evaporation of the tungsten filament compared to operating it in a vacuum. This allows for greater temperatures and therefore greater efficacy with less reduction in filament life.
Ans: operating it in a vacuum

Extract the answer to the question from the following context. Question: Who was the latest minister described in the text? Context: The monarchs of England and the United Kingdom had ministers in whom they placed special trust and who were regarded as the head of the government. Examples were Thomas Cromwell under Henry VIII; William Cecil, Lord Burghley under Elizabeth I; Clarendon under Charles II and Godolphin under Queen Anne. These ministers held a variety of formal posts, but were commonly known as "the minister", the "chief minister", the "first minister" and finally the "prime minister".
Ans: Godolphin

Extract the answer to the question from the following context. Question: Individuals that are descended from countries in the continent of Africa are? Context: About five percent of the population are of full-blooded indigenous descent, but upwards to eighty percent more or the majority of Hondurans are mestizo or part-indigenous with European admixture, and about ten percent are of indigenous or African descent. The main concentration of indigenous in Honduras are in the rural westernmost areas facing Guatemala and to the Caribbean Sea coastline, as well on the Nicaraguan border. The majority of indigenous people are Lencas, Miskitos to the east, Mayans, Pech, Sumos, and Tolupan.
Ans: African

Extract the answer to the question from the following context. Question: How would you travel to the reservoir from the plant? Context: The Zipingpu Hydropower Plant (simplified Chinese: 紫坪铺水库; traditional Chinese: 紫坪鋪水庫) located 20 km east of the epicenter was damaged. A recent inspection indicated that the damage was less severe than initially feared, and it remains structurally stable and safe. The Tulong reservoir upstream is in danger of collapse. About 2,000 troops have been allocated to Zipingpu, trying to release the pressure through spillway. In total, 391 dams, most of them small, were reported damaged by the quake.
Ans: upstream