Problem: Printed circuit board:

Areas that should not be soldered may be covered with solder resist (solder mask). One of the most common solder resists used today is called "LPI" (liquid photoimageable solder mask). A photo-sensitive coating is applied to the surface of the PWB, then exposed to light through the solder mask image film, and finally developed where the unexposed areas are washed away. Dry film solder mask is similar to the dry film used to image the PWB for plating or etching. After being laminated to the PWB surface it is imaged and develop as LPI. Once common but no longer commonly used because of its low accuracy and resolution is to screen print epoxy ink. Solder resist also provides protection from the environment.

What solder resist with a four-word name is a popular choice in the industry?
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A: liquid photoimageable solder mask

Problem: Political party:

A political party is typically led by a party leader (the most powerful member and spokesperson representing the party), a party secretary (who maintains the daily work and records of party meetings), party treasurer (who is responsible for membership dues) and party chair (who forms strategies for recruiting and retaining party members, and also chairs party meetings). Most of the above positions are also members of the party executive, the leading organization which sets policy for the entire party at the national level. The structure is far more decentralized in the United States because of the separation of powers, federalism and the multiplicity of economic interests and religious sects. Even state parties are decentralized as county and other local committees are largely independent of state central committees. The national party leader in the U.S. will be the president, if the party holds that office, or a prominent member of Congress in opposition (although a big-state governor may aspire to that role). Officially, each party has a chairman for its national committee who is a prominent spokesman, organizer and fund-raiser, but without the status of prominent elected office holders.

Do political parties have a Party leader?
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A: A political party is typically led by a party leader

Problem: San Diego:

The original town of San Diego was located at the foot of Presidio Hill, in the area which is now Old Town San Diego State Historic Park. The location was not ideal, being several miles away from navigable water. In 1850, William Heath Davis promoted a new development by the Bay shore called "New San Diego", several miles south of the original settlement; however, for several decades the new development consisted only a few houses, a pier and an Army depot. In the late 1860s, Alonzo Horton promoted a move to the bayside area, which he called "New Town" and which became Downtown San Diego. Horton promoted the area heavily, and people and businesses began to relocate to New Town because of its location on San Diego Bay convenient to shipping. New Town soon eclipsed the original settlement, known to this day as Old Town, and became the economic and governmental heart of the city. Still, San Diego remained a relative backwater town until the arrival of a railroad connection in 1878.

Who was largely responsible for the population growth of Downtown San Francisco?
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A: unanswerable

Problem: John von Neumann:

Stochastic computing was first introduced in a pioneering paper by von Neumann in 1953. However, the theory could not be implemented until advances in computing of the 1960s. He also created the field of cellular automata without the aid of computers, constructing the first self-replicating automata with pencil and graph paper. The concept of a universal constructor was fleshed out in his posthumous work Theory of Self Reproducing Automata. Von Neumann proved that the most effective way of performing large-scale mining operations such as mining an entire moon or asteroid belt would be by using self-replicating spacecraft, taking advantage of their exponential growth. His rigorous mathematical analysis of the structure of self-replication (of the semiotic relationship between constructor, description and that which is constructed), preceded the discovery of the structure of DNA. Beginning in 1949, von Neumann's design for a self-reproducing computer program is considered the world's first computer virus, and he is considered to be the theoretical father of computer virology.

When was stochastic computing introduced?
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A:
1953