I know that the answer to the question "What is the most important consideration in the operational design of a lighting fixture?" is in "Lighting fixtures come in a wide variety of styles for various functions. The most important functions are as a holder for the light source, to provide directed light and to avoid visual glare. Some are very plain and functional, while some are pieces of art in themselves. Nearly any material can be used, so long as it can tolerate the excess heat and is in keeping with safety codes.". Can you tell me what it is?
----
Answer: tolerate the excess heat

I know that the answer to the question "Who was the biggest threat to the Ming, Khorchin Mongol or Nurhachi?" is in "Relocating his court from Jianzhou to Liaodong provided Nurhachi access to more resources; it also brought him in close contact with the Khorchin Mongol domains on the plains of Mongolia. Although by this time the once-united Mongol nation had long since fragmented into individual and hostile tribes, these tribes still presented a serious security threat to the Ming borders. Nurhachi's policy towards the Khorchins was to seek their friendship and cooperation against the Ming, securing his western border from a powerful potential enemy.". Can you tell me what it is?
----
Answer: Nurhachi

I know that the answer to the question "What started and ended within a 2 year period?" is in "From 1228, after of the Livonian Crusade, through the 1560s, Estonia was part of Terra Mariana, established on 2 February 1207 as a principality of the Holy Roman Empire and proclaimed by Pope Innocent III in 1215 as subject to the Holy See. The southern parts of the country were conquered by Livonian Brothers of the Sword who joined the Teutonic Order in 1237 and became its branch known as the Livonian Order. The Duchy of Estonia was created out of the northern parts of the country and was a direct dominion of the King of Denmark from 1219 until 1346, when it was sold to the Teutonic Order and became part of the Ordenstaat. In 1343, the people of northern Estonia and Saaremaa rebelled against German rule in the St. George's Night Uprising, which was put down by 1345. The unsuccessful rebellion led to a consolidation of power for the Baltic German minority. For the subsequent centuries they remained the ruling elite in both cities and in the countryside.". Can you tell me what it is?
----
Answer:
the people of northern Estonia and Saaremaa rebelled against German rule