Cassava (/kəˈsɑːvə/), Manihot esculenta, or manioc




Дата канвертавання22.04.2016
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Cassava (/kəˈsɑːvə/), Manihot esculenta, or manioc, a woody shrub of the Euphorbiaceae (spurge) family native to South America, is extensively cultivated as an annualcrop in tropical and subtropical regions for its edible starchy tuberous root, a major source of carbohydrates. It differs from the similarly spelled yucca, an unrelated fruit-bearing shrub in the Asparagaceae family. Cassava, when dried to a powdery (or pearly) extract, is called tapioca; its fermented, flaky version is named garri.

Cassava is the third largest source of food carbohydrates in the tropics, after rice and maize. Cassava is a major staple food in the developing world, providing a basic diet for over half a billion people. It is one of the most drought-tolerant crops, capable of growing on marginal soils. Nigeria is the world's largest producer of cassava, while Thailand is the largest exporter of dried cassava.

Cassava is classified as sweet or bitter. Farmers often prefer the bitter varieties because they deter pests, animals, and thieves. Like other roots and tubers, both bitter and sweet varieties of cassava contain antinutritional factors and toxins. It must be properly prepared before consumption. Improper preparation of cassava can leave enough residual cyanide to cause acute cyanide intoxication and goiters, and may even cause ataxia or partial paralysis. The more toxic varieties of cassava are a fall-back resource (a "food security crop") in times of famin

The files on the basis of which it will perform calculations CSV files with the extension (please see them in a notebook). Excel divides the data into columns automatically, based on the commas.


The files contain data for 10 years. Eg. CASSAVA81PROD.CSV means the data from the years 1981 to 1990 for the production of cassava, CASSAVA71YIELD.CSV performance data from the years 1971-1980. Files whose names contain the number 99 contain data for the entire world in one - 1999 - a year.


Tasks.

After having broken down into 3 groups, please:

1. Collect a single sheet of production data for the years 1961 to 1999 (Group I - area, group II - performance, group III production).

2. Make a list of five-year averages for each country.



3. Create a chart for selected two countries based on data from 5 years.


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