Napoleon's codes (1804) were a set of civil codes that had to be practiced by the French society. The aim of the code was to reform the French society, in areas such as family, property, civil procedure etc.
Established equality before law, Abolished all privileges based on birth, Granted the right to property to French citizens, Simplified administrative divisions, Abolished feudal system and freed peasants from serfdom, Removed restrictions on guilds in towns, Improved transport and communication.

Contour ploughing or contour farming or Contour bunding is the farming practice of plowing and/or planting across a slope following its elevation contour lines. These contour lines create a water break which reduces the formation of rills and gullies during times of heavy water run-off; which is a major cause of soil erosion. The water break also allows more time for the water to settle into the soil.

The Non-Cooperation Movement was a significant but short phase of the Indian independence movement from British rule. It was led by Mahatma Gandhi after the Jallianwala Bagh Massacre and lasted from 1920 to February 1922.
Foreign goods were boycotted, liquor shops were picketed and bonfires were lit of foreign cloth.

Revolutionaries spread the idea in Europe after 1815 in the following ways:

1. The autocratic rule after 1815 had caused fear of repression so the liberal-nationalists started to work underground.
2. They established many secret societies to train revolutionaries and spread their ideas.
3. They opposed monarchical forms of governments that were established after the Vienna Congress.
4. They fought for liberty and freedom and thought the creation of nation-state as a necessary part of their struggle for freedom.
5. Being a revolutionary was a commitment to struggle for liberty and freedom and they considered nation states necessary for it to happen. 
6. They formed secret societies to spread ideas and train revolutionaries. For eg, Giuseppe Mazzini founded secret societies like Young Italy and Young Europe for the unification of fragmented Italy.
7. Following Mazzini’s model, secret societies were set up in Germany, France, Switzerland and Poland.
8. Liberalism and nationalism brought revolution in many regions of Europe like the provinces of the Ottoman Empire, Ireland, Poland besides Italy and Germany.

Underground mining is very risky as every year a large number of miners die due to:

1. Explosions, too, trigger casualties when ventilation systems fail to effectively remove exhaust from mining equipment, coal dust and natural underground gas leaks .Emission of poisonous gases such as methane
2. Accidental fires in the tunnels.
3. Flooding due to seepage of underground water.
4. Caving of roofs and tunnels due to water.
5. Continually breathing in mineral dust can cause lung diseases like pneumoconiosis or the dreaded black lung.

Following are the factors which led to the rise of Nationalism in Europe:

1. Decline of feudalism: Feudal lords were a great tumbling block in the way of the rise of the nationalism feelings among the people. But their mutual warfare and crusades weakened them.
2. Weakness of Papacy and the Roman Empire: The renaissance and reformation movements led to awakening among the people and weakened the authority of the pope and the Holy Roman Empire. Consequently, national churches and national states were established in many countries.
3. Foreign rule: In certain countries, foreign rule also played an important part in the growth of nationalism.
4. Reaction against injustice: Sometimes reaction against the arbitrary rule of unjust monarchs also gave birth to the feeling of nationalism.
5. Contribution of great writers: The writings of great poets, politicians and philosophers like Machiavelli, J.S. Mill, Fitch, Mazzini, Garibaldi etc. went a long way in rousing political consciousness and national sprit among the people.

Gross Enrollment Ratio is a statistical measure used in the education sector, and formerly by the UN in its Education Index, to determine the number of students enrolled in school at several different grade levels, and use it to show the ratio of the number of students who live in that country to those who qualify for the particular grade level.

Nationalism refers to the feeling of oneness and common consciousness that emerges when people living in a common territory share the same historical, political and cultural backgrounds. People may be speaking different languages (as in case of India) but the love for their nation keeps them together.