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London is one of the leading tourist destinations in the world and in 2015 was ranked as the most visited city in the world with over 65 million visits. It is also the top city in the world by visitor cross-border spending, estimated at US$20.23 billion in 2015 Tourism is one of London's prime industries, employing the equivalent of 350,000 full-time workers in 2003, and the city accounts for 54% of all inbound visitor spend in UK. As of 2016 London is rated as the world top ranked city destination by TripAdvisor users.
How many US dollars are estimated to have been spent in London by visitors from other countries?
A: $20.23 billion

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Kant argued against all three forms of materialism, subjective idealism (which he contrasts with his "transcendental idealism") and dualism. However, Kant also argues that change and time require an enduring substrate, and does so in connection with his Refutation of Idealism. Postmodern/poststructuralist thinkers also express a skepticism about any all-encompassing metaphysical scheme. Philosopher Mary Midgley, among others, argues that materialism is a self-refuting idea, at least in its eliminative form.
Who agreed with all three forms of materialism?
A: unanswerable

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Nigeria is often referred to as the "Giant of Africa", owing to its large population and economy. With approximately 182 million inhabitants, Nigeria is the most populous country in Africa and the seventh most populous country in the world. Nigeria has one of the largest populations of youth in the world. The country is viewed as a multinational state, as it is inhabited by over 500 ethnic groups, of which the three largest are the Hausa, Igbo and Yoruba; these ethnic groups speak over 500 different languages, and are identified with wide variety of cultures. The official language is English. Nigeria is divided roughly in half between Christians, who live mostly in the southern part of the country, and Muslims in the northern part. A minority of the population practise religions indigenous to Nigeria, such as those native to Igbo and Yoruba peoples.
What is Nigeria's official language?
A: English

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Furthermore, the amount of time adolescents spend on work and leisure activities varies greatly by culture as a result of cultural norms and expectations, as well as various socioeconomic factors. American teenagers spend less time in school or working and more time on leisure activitieswhich include playing sports, socializing, and caring for their appearancethan do adolescents in many other countries. These differences may be influenced by cultural values of education and the amount of responsibility adolescents are expected to assume in their family or community.
Do American teenagers spend more or less time in shool than adolescents in other countires?
A:
less