An antenna transmits and receives radio waves with a particular polarization which can be reoriented by tilting the axis of the antenna in many (but not all) cases. The physical size of an antenna is often a practical issue, particularly at lower frequencies (longer wavelengths). Highly directional antennas need to be significantly larger than the wavelength. Resonant antennas usually use a linear conductor (or element), or pair of such elements, each of which is about a quarter of the wavelength in length (an odd multiple of quarter wavelengths will also be resonant). Antennas that are required to be small compared to the wavelength sacrifice efficiency and cannot be very directional. Fortunately at higher frequencies (UHF, microwaves) trading off performance to obtain a smaller physical size is usually not required.
What is the essential difference in radio waves transmitted by an antenna?
polarization

Input: Bird
The ability of birds to return to precise locations across vast distances has been known for some time; in an experiment conducted in the 1950s a Manx shearwater released in Boston returned to its colony in Skomer, Wales, within 13 days, a distance of 5,150 km (3,200 mi). Birds navigate during migration using a variety of methods. For diurnal migrants, the sun is used to navigate by day, and a stellar compass is used at night. Birds that use the sun compensate for the changing position of the sun during the day by the use of an internal clock. Orientation with the stellar compass depends on the position of the constellations surrounding Polaris. These are backed up in some species by their ability to sense the Earth's geomagnetism through specialised photoreceptors.

Some species use specialised photoreceptors to sense what?
Output: the Earth's geomagnetism

Input: Article: With the occupation by Napoleon, Portugal began a slow but inexorable decline that lasted until the 20th century. This decline was hastened by the independence in 1822 of the country's largest colonial possession, Brazil. In 1807, as Napoleon's army closed in on Lisbon, the Prince Regent Joao VI of Portugal transferred his court to Brazil and established Rio de Janeiro as the capital of the Portuguese Empire. In 1815, Brazil was declared a Kingdom and the Kingdom of Portugal was united with it, forming a pluricontinental State, the United Kingdom of Portugal, Brazil and the Algarves.

Now answer this question: In what year did Brazil become independent from Portugal?

Output: 1822

Article: In response to the September 11 attacks, and as part of the Global War on Terror, U.S. and NATO forces invaded Afghanistan in October 2001, displacing the Taliban government. The U.S. Army also led the combined U.S. and allied invasion of Iraq in 2003. It served as the primary source for ground forces with its ability to sustain short and long-term deployment operations. In the following years the mission changed from conflict between regular militaries to counterinsurgency, resulting in the deaths of more than 4,000 U.S service members (as of March 2008) and injuries to thousands more. 23,813 insurgents were killed in Iraq between 20032011.

Question: How many Iraqi insurgents were killed from 2003-2011?
Ans: 23,813

Here is a question about this article: The decline of the city reached its nadir with the War of Spanish Succession (17021709) that marked the end of the political and legal independence of the Kingdom of Valencia. During the War of the Spanish Succession, Valencia sided with Charles of Austria. On 24 January 1706, Charles Mordaunt, 3rd Earl of Peterborough, 1st Earl of Monmouth, led a handful of English cavalrymen into the city after riding south from Barcelona, capturing the nearby fortress at Sagunt, and bluffing the Spanish Bourbon army into withdrawal.
What is the answer to this question: What did Mordaunt capture on his way from Barcelona?
****
So... fortress at Sagunt

Article: In 2002, Elizabeth marked her Golden Jubilee. Her sister and mother died in February and March respectively, and the media speculated whether the Jubilee would be a success or a failure. She again undertook an extensive tour of her realms, which began in Jamaica in February, where she called the farewell banquet "memorable" after a power cut plunged the King's House, the official residence of the governor-general, into darkness. As in 1977, there were street parties and commemorative events, and monuments were named to honour the occasion. A million people attended each day of the three-day main Jubilee celebration in London, and the enthusiasm shown by the public for the Queen was greater than many journalists had expected.

Question: What group was surprised by the public's approval of the Queen?
Ans:
journalists