Read the given passage carefully and answer the following five questions:

The Silk Route is an early example of long distance trade connecting Rome to China-along the 6,000 km route. The traders transported Chinese silk, Roman wool and precious metals and many other high value commodities from intermediate points in India, Persia and Central Asia.

After the disintegration of the Roman Empire, European commerce grew during twelfth and thirteenth century with the development of ocean going warships trade between Europe and Asia grew and the Americas were discovered.

Fifteenth century onwards, the European colonialism began and along with trade of exotic commodities, a new form of trade emerged which was called slave trade. The Portuguese, Dutch, Spaniards, and British captured African natives and forcefully transported them to the newly discovered Americas for their labour in the plantations, Slave trade was a lucrative business for more than two hundred years till it was abolished in Denmark in 1792, Great Britain in 1807 and United States in 1808.

After the Industrial Revolution, the demand for raw material like grains, meat, wool also expanded, but their monetary value declined in relation to the manufactured goods. The industrialised nations imported primary products as raw materials and exported the value added finished products back to the non-industrialised nations.

Transportation of grains, meat, wool expanded after______________.

Industrial Revolution