Problem: Please answer a question about the following article about Antenna (radio):
When an electromagnetic wave strikes a plane surface such as the ground, part of the wave is transmitted into the ground and part of it is reflected, according to the Fresnel coefficients. If the ground is a very good conductor then almost all of the wave is reflected (180 out of phase), whereas a ground modeled as a (lossy) dielectric can absorb a large amount of the wave's power. The power remaining in the reflected wave, and the phase shift upon reflection, strongly depend on the wave's angle of incidence and polarization. The dielectric constant and conductivity (or simply the complex dielectric constant) is dependent on the soil type and is a function of frequency.
Is the ground has a great conductor, how much of the wave will be reflected?
A: 180 out of phase
Problem: Please answer a question about the following article about Valencia:
The inevitable march to civil war and the combat in Madrid resulted in the removal of the capital of the Republic to Valencia. On 6 November 1936 the city became the capital of Republican Spain under the control of the prime minister Manuel Azana; the government moved to the Palau de Benicarlo, its ministries occupying various other buildings. The city was heavily bombarded by air and sea, necessitating the construction of over two hundred bomb shelters to protect the population. On 13 January 1937 the city was first shelled by a vessel of the Fascist Italian Navy, which was blockading the port by the order of Benito Mussolini. The bombardment intensified and inflicted massive destruction on several occasions; by the end of the war the city had survived 442 bombardments, leaving 2,831 dead and 847 wounded, although it is estimated that the death toll was higher, as the data given are those recognised by Francisco Franco's government. The Republican government passed to Juan Negrin on 17 May 1937 and on 31 October of that year moved to Barcelona. On 30 March 1939 Valencia surrendered and the Nationalist troops entered the city. The postwar years were a time of hardship for Valencians. During Franco's regime speaking or teaching Valencian was prohibited; in a significant reversal it is now compulsory for every schoolchild in Valencia.
Where did the government relocate to in 1937?
A: Barcelona
Problem: Please answer a question about the following article about Multiracial American:
The writer Sherrel W. Stewart's assertion that "most" African Americans have significant Native American heritage, is not supported by genetic researchers who have done extensive population mapping studies. The TV series on African-American ancestry, hosted by the scholar Henry Louis Gates, Jr., had genetics scholars who discussed in detail the variety of ancestries among African Americans. They noted there is popular belief in a high rate of Native American admixture that is not supported by the data that has been collected. (Reference is coming)
Who disproved Sherrel's hypothesis?
A: genetic researchers who have done extensive population mapping studies
Problem: Please answer a question about the following article about Labour Party (UK):
The Black Wednesday economic disaster in September 1992 left the Conservative government's reputation for monetary excellence in tatters, and by the end of that year Labour had a comfortable lead over the Tories in the opinion polls. Although the recession was declared over in April 1993 and a period of strong and sustained economic growth followed, coupled with a relatively swift fall in unemployment, the Labour lead in the opinion polls remained strong. However, Smith died from a heart attack in May 1994.
What did Smith die of?
A:
a heart attack