Read the following passage and answer questions (1-4) using information from it:
In Bangladesh folk music has great variety, with songs being composed on the culture, festivals, views of life, natural beauty, rivers and rural and riverine life. These songs are also about social inequality and poverty, about the material world and the supernatural. Mystical songs have been composed using the metaphors of river and boats. Since the country is basically riverine ,the bhatiyali forms an important genre of folk music .Folk music is formed and developed according to the environment. Difference in the natural environment are affected in the people of the different regions. Bangladeshi folk music therefore varies from region to region. Thus there are the northern Bhawaiya, the eastern Bhatiyali and the southwestern Baui songs. Folk songs may be sung individually or in chorus. Folk songs sung individually include Baui, Bhatiyali, Murshidi and Marfati , while songs sung in choros include Kabigan, Leto ,Alkap and Gambhira. Some songs are regional in character, but others are common to both Bangladesh and West Bengal.
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