Problem: Republic of the Congo:

Congo-Brazzaville has had a multi-party political system since the early 1990s, although the system is heavily dominated by President Denis Sassou Nguesso; he has lacked serious competition in the presidential elections held under his rule. Sassou Nguesso is backed by his own Congolese Labour Party (French: Parti Congolais du Travail) as well as a range of smaller parties.

Since when has Congo-Brazzaville has a single party political system?
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A: unanswerable


Problem: The aggressive policies of Lord Wellesley and the Marquis of Hastings led to the Company gaining control of all India (except for the Punjab and Sindh), and some part of the then kingdom of Nepal under the Sugauli Treaty. The Indian Princes had become vassals of the Company. But the expense of wars leading to the total control of India strained the Company's finances. The Company was forced to petition Parliament for assistance. This was the background to the Charter Act of 1813 which, among other things:
EIC reached out to parliament for help with finances. this lead to which Act?
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Answer: Charter Act of 1813


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The United States Congress declared war on Mexico on May 13, 1846 after only having a few hours to debate. Although President José Mariano Paredes's issuance of a manifesto on May 23 is sometimes considered the declaration of war, Mexico officially declared war by Congress on July 7. After the American invasion of New Mexico, Chihuahua sent 12,000 men led by Colonel Vidal to the border to stop the American military advance into the state. The Mexican forces being impatient to confront the American forces passed beyond El Paso del Norte about 20 miles (32 km) north along the Rio Grande. The first battle that Chihuahua fought was the battle of El Bracito; the Mexican forces consisting of 500 cavalry and 70 infantry confronted a force of 1,100–1,200 Americans on December 25, 1846. The battle ended badly by the Mexican forces that were then forced to retreat back into the state of Chihuahua. By December 27, 1846, the American forces occupied El Paso Del Norte. General Doniphan maintained camp in El Paso Del Norte awaiting supplies and artillery which he received in February 1847.
Who declared war on Mexico in 1846?
A: The United States


Context and question: The first Roman republican wars were wars of both expansion and defence, aimed at protecting Rome itself from neighbouring cities and nations and establishing its territory in the region. Initially, Rome's immediate neighbours were either Latin towns and villages, or else tribal Sabines from the Apennine hills beyond. One by one Rome defeated both the persistent Sabines and the local cities, both those under Etruscan control and those that had cast off their Etruscan rulers. Rome defeated Latin cities in the Battle of Lake Regillus in 496 BC, the Battle of Mons Algidus in 458 BC, the Battle of Corbione in 446 BC, the Battle of Aricia, and especially the Battle of the Cremera in 477 BC wherein it fought against the most important Etruscan city of Veii.
In what year did Rome claim victory against the city of Veii?
Answer: 477 BC


Question: Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use[citation needed]. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloys date to 3000 BC. The Bronze Age began in Southeastern Europe around 3700–3300 BC, in Northwestern Europe about 2500 BC. It ended with the beginning of the Iron Age, 2000–1000 BC in the Near East, 600 BC in Northern Europe. The transition between the Neolithic period and the Bronze Age was formerly termed the Chalcolithic period (copper-stone), with copper tools being used with stone tools. This term has gradually fallen out of favor because in some parts of the world the Chalcolithic and Neolithic are coterminous at both ends. Brass, an alloy of copper and zinc, is of much more recent origin. It was known to the Greeks, but became a significant supplement to bronze during the Roman Empire.
Is there an answer to this question: What is an alloy of copper and brass?

Answer: unanswerable


Problem: Alexander Graham Bell:

After setting up his workshop, Bell continued experiments based on Helmholtz's work with electricity and sound. He also modified a melodeon (a type of pump organ) so that it could transmit its music electrically over a distance. Once the family was settled in, both Bell and his father made plans to establish a teaching practice and in 1871, he accompanied his father to Montreal, where Melville was offered a position to teach his System of Visible Speech.

What is a melodeon a kind of?
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A:
pump organ