This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

[EX Q]: Tesla was renowned for his achievements and showmanship, eventually earning him a reputation in popular culture as an archetypal "mad scientist". His patents earned him a considerable amount of money, much of which was used to finance his own projects with varying degrees of success.:121,154 He lived most of his life in a series of New York hotels, through his retirement. Tesla died on 7 January 1943. His work fell into relative obscurity after his death, but in 1960 the General Conference on Weights and Measures named the SI unit of magnetic flux density the tesla in his honor. There has been a resurgence in popular interest in Tesla since the 1990s.
[EX A]: What year did Tesla die? 

[EX Q]: By 287 BC, the economic condition of the average plebeian had become poor. The problem appears to have centered around widespread indebtedness. The plebeians demanded relief, but the senators refused to address their situation. The result was the final plebeian secession. The plebeians seceded to the Janiculum hill. To end the secession, a dictator was appointed. The dictator passed a law (the Lex Hortensia), which ended the requirement that the patrician senators must agree before any bill could be considered by the Plebeian Council. This was not the first law to require that an act of the Plebeian Council have the full force of law. The Plebeian Council acquired this power during a modification to the original Valerian law in 449 BC. The significance of this law was in the fact that it robbed the patricians of their final weapon over the plebeians. The result was that control over the state fell, not onto the shoulders of voters, but to the new plebeian nobility.
[EX A]: What was the economic status of your typical plebeian in 287 BC?

[EX Q]: The most familiar, and historically the oldest, types of glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. The term glass, in popular usage, is often used to refer only to this type of material, which is familiar from use as window glass and in glass bottles. Of the many silica-based glasses that exist, ordinary glazing and container glass is formed from a specific type called soda-lime glass, composed of approximately 75% silicon dioxide (SiO2), sodium oxide (Na2O) from sodium carbonate (Na2CO3), calcium oxide, also called lime (CaO), and several minor additives. A very clear and durable quartz glass can be made from pure silica, but the high melting point and very narrow glass transition of quartz make glassblowing and hot working difficult. In glasses like soda lime, the compounds added to quartz are used to lower the melting temperature and improve workability, at a cost in the toughness, thermal stability, and optical transmittance.
[EX A]:
Which kinds of glass existed the furthest in the past?