Article: Lasers emitting in the green part of the spectrum are widely available to the general public in a wide range of output powers. Green laser pointers outputting at 532 nm (563.5 THz) are relatively inexpensive compared to other wavelengths of the same power, and are very popular due to their good beam quality and very high apparent brightness. The most common green lasers use diode pumped solid state (DPSS) technology to create the green light. An infrared laser diode at 808 nm is used to pump a crystal of neodymium-doped yttrium vanadium oxide (Nd:YVO4) or neodymium-doped yttrium aluminium garnet (Nd:YAG) and induces it to emit 281.76 THz (1064 nm). This deeper infrared light is then passed through another crystal containing potassium, titanium and phosphorus (KTP), whose non-linear properties generate light at a frequency that is twice that of the incident beam (563.5 THz); in this case corresponding to the wavelength of 532 nm ("green"). Other green wavelengths are also available using DPSS technology ranging from 501 nm to 543 nm. Green wavelengths are also available from gas lasers, including the helium–neon laser (543 nm), the Argon-ion laser (514 nm) and the Krypton-ion laser (521 nm and 531 nm), as well as liquid dye lasers. Green lasers have a wide variety of applications, including pointing, illumination, surgery, laser light shows, spectroscopy, interferometry, fluorescence, holography, machine vision, non-lethal weapons and bird control.

Question: What type of technology is used in the most common green lasers?
Ans: diode pumped solid state


Article: In the first volume of his Parerga and Paralipomena, Schopenhauer wrote his "Sketch of a History of the Doctrine of the Ideal and the Real". He defined the ideal as being mental pictures that constitute subjective knowledge. The ideal, for him, is what can be attributed to our own minds. The images in our head are what comprise the ideal. Schopenhauer emphasized that we are restricted to our own consciousness. The world that appears is only a representation or mental picture of objects. We directly and immediately know only representations. All objects that are external to the mind are known indirectly through the mediation of our mind. He offered a history of the concept of the "ideal" as "ideational" or "existing in the mind as an image".

Question: What did Schopenhauer believe were the only things we could know?
Ans: representations


Article: Beginning in February 1988, the Democratic Movement of Moldova (formerly Moldavia) organized public meetings, demonstrations, and song festivals, which gradually grew in size and intensity. In the streets, the center of public manifestations was the Stephen the Great Monument in Chişinău, and the adjacent park harboring Aleea Clasicilor (The "Alee of the Classics [of the Literature]"). On January 15, 1988, in a tribute to Mihai Eminescu at his bust on the Aleea Clasicilor, Anatol Şalaru submitted a proposal to continue the meetings. In the public discourse, the movement called for national awakening, freedom of speech, revival of Moldavian traditions, and for attainment of official status for the Romanian language and return to the Latin alphabet. The transition from "movement" (an informal association) to "front" (a formal association) was seen as a natural "upgrade" once a movement gained momentum with the public, and the Soviet authorities no longer dared to crack down on it.

Question: Which monument was a popular meeting place?
Ans: Stephen the Great Monument


Article: Raised in Chicago, West briefly attended art school before becoming known as a producer for Roc-A-Fella Records in the early 2000s, producing hit singles for artists such as Jay-Z and Alicia Keys. Intent on pursuing a solo career as a rapper, West released his debut album The College Dropout in 2004 to widespread commercial and critical success, and founded record label GOOD Music. He went on to explore a variety of different musical styles on subsequent albums that included the baroque-inflected Late Registration (2005), the arena-inspired Graduation (2007), and the starkly polarizing 808s & Heartbreak (2008). In 2010, he released his critically acclaimed fifth album, the maximalist My Beautiful Dark Twisted Fantasy, and the following year he collaborated with Jay-Z on the joint LP Watch the Throne (2011). West released his abrasive sixth album, Yeezus, to further critical praise in 2013. Following a series of recording delays and work on non-musical projects, West's seventh album, The Life of Pablo, was released in 2016.

Question: Who are some well known artists that Kanye produced for early in his career?
Ans:
Jay-Z and Alicia Keys