Problem: Although a resonant antenna has a purely resistive feed-point impedance at a particular frequency, many (if not most) applications require using an antenna over a range of frequencies. An antenna's bandwidth specifies the range of frequencies over which its performance does not suffer due to a poor impedance match. Also in the case of a Yagi-Uda array, the use of the antenna very far away from its design frequency reduces the antenna's directivity, thus reducing the usable bandwidth regardless of impedance matching.
What causes the frequencies outside of the bandwidth to be unusable?
The answer is the following: impedance match

Copper occurs naturally as native copper and was known to some of the oldest civilizations on record. It has a history of use that is at least 10,000 years old, and estimates of its discovery place it at 9000 BC in the Middle East; a copper pendant was found in northern Iraq that dates to 8700 BC. There is evidence that gold and meteoric iron (but not iron smelting) were the only metals used by humans before copper. The history of copper metallurgy is thought to have followed the following sequence: 1) cold working of native copper, 2) annealing, 3) smelting, and 4) the lost wax method. In southeastern Anatolia, all four of these metallurgical techniques appears more or less simultaneously at the beginning of the Neolithic c. 7500 BC. However, just as agriculture was independently invented in several parts of the world, copper smelting was invented locally in several different places. It was probably discovered independently in China before 2800 BC, in Central America perhaps around 600 AD, and in West Africa about the 9th or 10th century AD. Investment casting was invented in 45004000 BC in Southeast Asia and carbon dating has established mining at Alderley Edge in Cheshire, UK at 2280 to 1890 BC. Otzi the Iceman, a male dated from 33003200 BC, was found with an axe with a copper head 99.7% pure; high levels of arsenic in his hair suggest his involvement in copper smelting. Experience with copper has assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6000 and 3000 BC. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC.[citation needed]
Copper smelting resulted in the development of what other metal smelting?
iron smelting

Input: Chihuahua (state)
During the 14th century in the northeastern part of the state nomad tribes by the name of Jornado hunted bison along the Rio Grande; they left numerous rock paintings throughout the northeastern part of the state. When the Spanish explorers reached this area they found their descendants, Suma and Manso tribes. In the southern part of the state, in a region known as Aridoamerica, Chichimeca people survived by hunting, gathering, and farming between AD 300 and 1300. The Chichimeca are the ancestors of the Tepehuan people.

Along which river did they hunt bison?
Output: Rio Grande

Input: Article: Executive vice governor Wei Hong confirmed on November 21, 2008 that more than 90,000 people in total were dead or missing in the earthquake. He stated that 200,000 homes had been rebuilt, and 685,000 were under reconstruction, but 1.94 million households were still without permanent shelter. 1,300 schools had been reconstructed, with initial relocation of 25 townships, including Beichuan and Wenchuan, two of the most devastated areas. The government spent $441 billion on relief and reconstruction efforts.

Now answer this question: How many homes had been rebuilt?

Output: 200,000

Article: The last major building work took place during the reign of King George V when, in 1913, Sir Aston Webb redesigned Blore's 1850 East Front to resemble in part Giacomo Leoni's Lyme Park in Cheshire. This new, refaced principal facade (of Portland stone) was designed to be the backdrop to the Victoria Memorial, a large memorial statue of Queen Victoria, placed outside the main gates. George V, who had succeeded Edward VII in 1910, had a more serious personality than his father; greater emphasis was now placed on official entertaining and royal duties than on lavish parties. He arranged a series of command performances featuring jazz musicians such as the Original Dixieland Jazz Band (1919) the first jazz performance for a head of state, Sidney Bechet, and Louis Armstrong (1932), which earned the palace a nomination in 2009 for a (Kind of) Blue Plaque by the Brecon Jazz Festival as one of the venues making the greatest contribution to jazz music in the United Kingdom. George V's wife Queen Mary was a connoisseur of the arts, and took a keen interest in the Royal Collection of furniture and art, both restoring and adding to it. Queen Mary also had many new fixtures and fittings installed, such as the pair of marble Empire-style chimneypieces by Benjamin Vulliamy, dating from 1810, which the Queen had installed in the ground floor Bow Room, the huge low room at the centre of the garden facade. Queen Mary was also responsible for the decoration of the Blue Drawing Room. This room, 69 feet (21 metres) long, previously known as the South Drawing Room, has a ceiling designed specially by Nash, coffered with huge gilt console brackets.

Question: Who added and restored furniture to The Royal Collection?
Ans: Queen Mary

Input: Alaska
The climate in Southeast Alaska is a mid-latitude oceanic climate (Koppen climate classification: Cfb) in the southern sections and a subarctic oceanic climate (Koppen Cfc) in the northern parts. On an annual basis, Southeast is both the wettest and warmest part of Alaska with milder temperatures in the winter and high precipitation throughout the year. Juneau averages over 50 in (130 cm) of precipitation a year, and Ketchikan averages over 150 in (380 cm). This is also the only region in Alaska in which the average daytime high temperature is above freezing during the winter months.

In what region of Alaska is the daytime temperature above freezing during summer?
Output:
Southeast