Problem: and Camargo. In 1631 Juan Rangel de Biezma discovered a rich vein of silver, and subsequently established San Jose del Parral near the site. Parral remained an important economic and cultural center for the next 300 years. On December 8, 1659 Fray Garcia de San Francisco founded the mission of Nuestra Senora de Guadalupe de Mansos del Paso del Rio del Norte and founded the town El Paso Del Norte (present day Ciudad Juarez) in 1667. The Spanish society that developed in the region replaced the sparse population of indigenous peoples. The absence of servants and workers forged the spirit of northern people as self-dependent, creative people that defended their European heritage. In 1680 settlers from Santa Fe, New Mexico sought refuge in El Paso Del Norte for twelve years after fleeing the attacks from Pueblo tribes, but returned to Santa Fe in 1692 after Diego de Vargas recaptured the city and vicinity. In 1709, Antonio de Deza y Ulloa founded the state capital Chihuahua City; shortly after, the city became the headquarters for the regional mining offices of the Spanish crown known as Real de Minas de San Francisco de Cuellar in honor of the Viceroy of New Spain, Francisco Fernandez de la Cueva Enriquez, Duke of Alburquerque and the Marquee of Cuellar..
In which year did Sante Fe inhabitants return home from seeking refuge?
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Answer: 1692

Problem: Accounts of the use of leeches for the medically dubious practise of blood-letting have come from China around 30 AD, India around 200 AD, ancient Rome around 50 AD and later throughout Europe. In the 19th century medical demand for leeches was so high that some areas' stocks were exhausted and other regions imposed restrictions or bans on exports, and Hirudo medicinalis is treated as an endangered species by both IUCN and CITES. More recently leeches have been used to assist in microsurgery, and their saliva has provided anti-inflammatory compounds and several important anticoagulants, one of which also prevents tumors from spreading.
Which organizations list Hirudo medicinalis as extinct?
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Answer: unanswerable

Problem: Consider a half-wave dipole designed to work with signals 1 m wavelength, meaning the antenna would be approximately 50 cm across. If the element has a length-to-diameter ratio of 1000, it will have an inherent resistance of about 63 ohms. Using the appropriate transmission wire or balun, we match that resistance to ensure minimum signal loss. Feeding that antenna with a current of 1 ampere will require 63 volts of RF, and the antenna will radiate 63 watts (ignoring losses) of radio frequency power. Now consider the case when the antenna is fed a signal with a wavelength of 1.25 m; in this case the reflected current would arrive at the feed out-of-phase with the signal, causing the net current to drop while the voltage remains the same. Electrically this appears to be a very high impedance. The antenna and transmission line no longer have the same impedance, and the signal will be reflected back into the antenna, reducing output. This could be addressed by changing the matching system between the antenna and transmission line, but that solution only works well at the new design frequency.
What effect occurs when the signal is reflected back into the antenna?
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Answer:
reducing output