Question: There are quite a few different dielectrics that can be chosen to provide different insulating values depending on the requirements of the circuit. Some of these dielectrics are polytetrafluoroethylene (Teflon), FR-4, FR-1, CEM-1 or CEM-3. Well known pre-preg materials used in the PCB industry are FR-2 (phenolic cotton paper), FR-3 (cotton paper and epoxy), FR-4 (woven glass and epoxy), FR-5 (woven glass and epoxy), FR-6 (matte glass and polyester), G-10 (woven glass and epoxy), CEM-1 (cotton paper and epoxy), CEM-2 (cotton paper and epoxy), CEM-3 (non-woven glass and epoxy), CEM-4 (woven glass and epoxy), CEM-5 (woven glass and polyester). Thermal expansion is an important consideration especially with ball grid array (BGA) and naked die technologies, and glass fiber offers the best dimensional stability.
Is there an answer to this question: Thermal closure is an important what?

Answer: unanswerable


Question: As the Kulluk oil rig was being towed to the American state of Washington to be serviced in preparation for the 2013 drilling season, a winter storm on 27 December 2012 caused the towing crews, as well as the rescue service, to lose control of the situation. As of 1 January 2013, the Kulluk was grounded off the coast Sitkalidak Island, near the eastern end of Kodiak Island. Following the accident, a Fortune magazine contacted Larry McKinney, the executive director at the Harte Research Institute for Gulf of Mexico Studies at Texas A&M, and he explained that "A two-month delay in the Arctic is not a two-month delay ... A two-month delay could wipe out the entire drilling season."
Is there an answer to this question: How long did it take to tow the Kulluk to Washington state?

Answer: unanswerable


Question: The first task of a database designer is to produce a conceptual data model that reflects the structure of the information to be held in the database. A common approach to this is to develop an entity-relationship model, often with the aid of drawing tools. Another popular approach is the Unified Modeling Language. A successful data model will accurately reflect the possible state of the external world being modeled: for example, if people can have more than one phone number, it will allow this information to be captured. Designing a good conceptual data model requires a good understanding of the application domain; it typically involves asking deep questions about the things of interest to an organisation, like "can a customer also be a supplier?", or "if a product is sold with two different forms of packaging, are those the same product or different products?", or "if a plane flies from New York to Dubai via Frankfurt, is that one flight or two (or maybe even three)?". The answers to these questions establish definitions of the terminology used for entities (customers, products, flights, flight segments) and their relationships and attributes.
Is there an answer to this question: Asking questions about an organization's needs will help to create what?

Answer: definitions of the terminology used for entities


Question: To create green sparks, fireworks use barium salts, such as barium chlorate, barium nitrate crystals, or barium chloride, also used for green fireplace logs. Copper salts typically burn blue, but cupric chloride (also known as "campfire blue") can also produce green flames. Green pyrotechnic flares can use a mix ratio 75:25 of boron and potassium nitrate. Smoke can be turned green by a mixture: solvent yellow 33, solvent green 3, lactose, magnesium carbonate plus sodium carbonate added to potassium chlorate.
Is there an answer to this question: What type of copper salts are used in fireworks?

Answer:
unanswerable