. What were the main inventions of the industrial revolution? What changes did they bring about ?

The Industrial Revolution was a period of great industrialization that began in the late 18th century in Britain, leading to massive population growth and agricultural innovations, which laid the foundation for increased productivity, both with increased labor and a larger market for the products. There was a revolution in the production methods of the textile industry, especially with the advent of the steam engine and urban development, the influx of people from the countryside to the cities meant that there was an abundance of labor, which laid the foundation for the industrial cities of the nineteenth century.  The steam engine was also used in the new generation of transport, in locomotives and steamships. With the advent of steel as a building material along with a series of new discoveries in communication technology in the second half of the 19th century, the tone was set for the continued technological development of the 20th century.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.