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Between 1631 and 1890, the city tripled its area through land reclamation by filling in marshes, mud flats, and gaps between wharves along the waterfront. The largest reclamation efforts took place during the 19th century; beginning in 1807, the crown of Beacon Hill was used to fill in a 50-acre (20 ha) mill pond that later became the Haymarket Square area. The present-day State House sits atop this lowered Beacon Hill. Reclamation projects in the middle of the century created significant parts of the South End, the West End, the Financial District, and Chinatown. After The Great Boston Fire of 1872, workers used building rubble as landfill along the downtown waterfront. During the mid-to-late 19th century, workers filled almost 600 acres (2.4 km2) of brackish Charles River marshlands west of Boston Common with gravel brought by rail from the hills of Needham Heights. The city annexed the adjacent towns of South Boston (1804), East Boston (1836), Roxbury (1868), Dorchester (including present day Mattapan and a portion of South Boston) (1870), Brighton (including present day Allston) (1874), West Roxbury (including present day Jamaica Plain and Roslindale) (1874), Charlestown (1874), and Hyde Park (1912). Other proposals, for the annexation of Brookline, Cambridge, and Chelsea, were unsuccessful.
What famous disaster happened in Boston in 1872?
A: The Great Boston Fire of 1872

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The allies' most advanced technologies were showcased by the anti-aircraft defence against the German V-1 cruise missiles (V stands for Vergeltungswaffe, "retaliation weapon"). The 419th and 601st Antiaircraft Gun Battalions of the US Army were first allocated to the Folkestone-Dover coast to defend London, and then moved to Belgium to become part of the "Antwerp X" project. With the liberation of Antwerp, the port city immediately became the highest priority target, and received the largest number of V-1 and V-2 missiles of any city. The smallest tactical unit of the operation was a gun battery consisting of four 90 mm guns firing shells equipped with a radio proximity fuse. Incoming targets were acquired and automatically tracked by SCR-584 radar, developed at the MIT Rad Lab. Output from the gun-laying radar was fed to the M-9 director, an electronic analog computer developed at Bell Laboratories to calculate the lead and elevation corrections for the guns. With the help of these three technologies, close to 90% of the V-1 missiles, on track to the defence zone around the port, were destroyed.
Where did the US Army 419th and 601st relocate to as part of the Antwerp X project?
A: Belgium

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Catalan verbs are traditionally divided into three conjugations, with vowel themes -a-, -e-, -i-, the last two being split into two subtypes. However, this division is mostly theoretical. Only the first conjugation is nowadays productive (with about 3500 common verbs), whereas the third (the subtype of servir, with about 700 common verbs) is semiproductive. The verbs of the second conjugation are fewer than 100, and it is not possible to create new ones, except by compounding.
Which conjugation has about 3500 verbs?
A: first conjugation

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In single phase squirrel cage motors, the primary winding within the motor housing is not capable of starting a rotational motion on the rotor, but is capable of sustaining one. To start the motor, a secondary "start" winding has a series non-polarized starting capacitor to introduce a lead in the sinusoidal current. When the secondary (start) winding is placed at an angle with respect to the primary (run) winding, a rotating electric field is created. The force of the rotational field is not constant, but is sufficient to start the rotor spinning. When the rotor comes close to operating speed, a centrifugal switch (or current-sensitive relay in series with the main winding) disconnects the capacitor. The start capacitor is typically mounted to the side of the motor housing. These are called capacitor-start motors, that have relatively high starting torque. Typically they can have up-to four times as much starting torque than a split-phase motor and are used on applications such as compressors, pressure washers and any small device requiring high starting torques.
 Where is the start capacitor commonly mounted?
A:
unanswerable