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In 494 BC, the city was at war with two neighboring tribes. The plebeian soldiers refused to march against the enemy, and instead seceded to the Aventine Hill. The plebeians demanded the right to elect their own officials. The patricians agreed, and the plebeians returned to the battlefield. The plebeians called these new officials "plebeian tribunes". The tribunes would have two assistants, called "plebeian aediles". During the 5th century BC, a series of reforms were passed. The result of these reforms was that any law passed by the plebeian would have the full force of law. In 443 BC, the censorship was created. From 375 BC to 371 BC, the republic experienced a constitutional crisis during which the tribunes used their vetoes to prevent the election of senior magistrates.
In what year was the city in conflict with two nearby tribes?
A: 494 BC

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Canadian defence policy today is based on the Canada First Defence Strategy, introduced in 2008. Based on that strategy, the Canadian military is oriented and being equipped to carry out six core missions within Canada, in North America and globally. Specifically, the Canadian Armed Forces are tasked with having the capacity to:
When was the Canada First Defence Strategy introduced?
A: 2008

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Since the latewood of a growth ring is usually darker in color than the earlywood, this fact may be used in judging the density, and therefore the hardness and strength of the material. This is particularly the case with coniferous woods. In ring-porous woods the vessels of the early wood not infrequently appear on a finished surface as darker than the denser latewood, though on cross sections of heartwood the reverse is commonly true. Except in the manner just stated the color of wood is no indication of strength.
Which property of a tree's wood that gives clues about its strength and hardness can be judged by it's color?
A: density

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Houston has mild winters in contrast to most areas of the United States. In January, the normal mean temperature at Intercontinental Airport is 53.1 F (11.7 C), while that station has an average of 13 days with a low at or below freezing. Snowfall is rare. Recent snow events in Houston include a storm on December 24, 2004 when one inch (2.5 cm) of snow accumulated in parts of the metro area. Falls of at least one inch on both December 10, 2008 and December 4, 2009 marked the first time measurable snowfall had occurred in two consecutive years in the city's recorded history. The coldest temperature officially recorded in Houston was 5 F (15 C) on January 18, 1940. Houston has historically received an ample amount of rainfall, averaging about 49.8 in (1,260 mm) annually per 19812010 normals. Localized flooding often occurs, owing to the extremely flat topography and widespread typical clay-silt prairie soils, which do not drain quickly.
What type of weather is a rarity in Houston?
A:
Snowfall