• The primary function of money is to act as a medium of exchange between two parties involved in a transaction. It avoids the practical problems of wastage of time and resources involved in the barter system of exchange and it improves the efficiency of the transaction.
• It promotes allocation efficiency in the trade and production of goods and services.  In case of the barter system, the sale and purchase of goods occurs at the same time. Their sale and purchase value also remains equal at that point.
• A person can purchase or sell goods with cash without selling or purchasing any good at that point, after money came into existence. Thus, the act of purchase and sale has been separated.
• Thereby the medium of exchange facilitated sale and purchase very easily in terms of monetary value. 

Question:
Write on the social change in the city in the eighteenth century.

Answer:
The social change in the city in the eighteenth century:
(i)Ties between members of households loosened, and among the working class the institution of marriage tended to break down.
(ii)Women of the upper and middle classes in Britain, on the other hand, faced increasingly higher levels of isolation,although their lives were made easier by domestic maids who cooked, cleaned and cared for young children on low
wages.
(iii)Women who worked for wages had some control over their lives, particularly among the lower social classes.

The seven islands of Bombay were joined into one landmass only over a period of time.
(i)The earliest project began in 1784. The Bombay governor William Hornby approved the building of the great sea wall
which prevented the flooding of the low-lying areas of Bombay.
(ii)Since then, there have been several reclamation projects. The need for additional commercial space in the mid-
nineteenth century led to the formulation of several plans, both by government and private companies, for the
reclamation of more land from the sea.
(iii)Private companies became more interested in taking financial risks. In 1864, the Back Bay Reclamation Company won
the right to reclaim the western foreshore from the tip of Malabar Hill to the end of Colaba. Reclamation often meant the
levelling of the hills around Bombay.
(iv)As the population continued to increase rapidly in the early twentieth century, every bit of the available area was built
over and new areas were reclaimed from the sea.
(v)A successful reclamation project was undertaken by the Bombay Port Trust, which built a dry dock between 1914 and
1918 and used the excavated earth to create the 22-acre Ballard Estate. Subsequently, the famous Marine Drive of
Bombay was developed.

Both London and Bombay ( Mumbai) are industrial cities .both had dense population due to migration of workers in search of jobs in cities, towns.Recreation and Entertainment facilities were available to wealthy individuals.Both had good education system.Both the cities tried hard to cope up with providing housing facilities to growing population in the early 18th and 19th centuries.Both had heritage buildings which are preserved even today

Differences

1 Mumbai (Bombay) is the port city with number of top industries functioning in itIt is commutable on road, rail, sea etc 2Traffic problem persists in Bombay even today 3 housing conditions is under developing stage in Bombay 4Bombay is the birthplace of Hindi cinema and it is considered as the modern city that follows western culture to greater levels

​​London

1.  Majority of people who lived in London in the early 19th century were migrants, workers, labourers etc 
2.  London had well developed underground railway transport which solved commuting problems of the working class public 
3.  Women belonging to lower social sections of society worked when compared with upper caste women
4.  Wealthy people of London celebrated annual event by name, London Season which was their main source of entertainment

• The first Indian newspaper was the weekly Bengal Gazette which was brought out by Gangadhar Bhattacharya.
• Many existing religious practices were criticized. Rammohun Roy published Sambad Kaumudi from 1821 to criticize the orthodox views in the Hinduism.
• The Hindu orthodoxy commissioned the Samachar Chandrika to counter his opinions. In 1822, publication of two Persian newspapers began, viz. Jam – i- Jahan Nama and Shamsul Akhbar. Bombay Samachar; a Gujarati newspaper appeared in the same year.
• In north India, the ulama began to publish cheap lithographic prints which contained Persian and Urdu translations of holy scriptures. They also published religious newspapers and tracts.
• The Deoband Seminary was founded in 1867. It published thousands upon thousands fatwas about proper conduct in the life of Muslims.

Print Culture and Public Debate in Europe:

• The new printed literature was criticized as it was feared that if there was no control over what was printed and read, then rebellious and irreligious thoughts might spread. Those who disagreed with established authorities could now print and circulate ideas.
• 1517: A religious reformer, Martin Luther wrote ‘Ninety-five Theses’ criticizing many of the practices and rituals of the Roman Catholic Church.
•  Luther’s writings were immediately reproduced in vast numbers and read widely. This led to a division within the Church and to the beginning of the Protestant Reformation.
•  Several scholars think that print brought about a new intellectual atmosphere and helped spread the new ideas that led to the Reformation.
•  1558: The Roman Church, troubled by effects of popular readings and questionings of faith, imposed several controls over publishers and booksellers and began to maintain an Index of Prohibited Books.
• In France-Print popularized the ideas of the Enlightenment thinkers. They attacked the sacred authority of the Church and the despotic powers of the state; thus, eroding the legitimacy of a social order based on tradition. Voltaire and Rousseau were widely read.

In India:From the early 19th century, there were intense debates around religious issues. Some criticized existing practices and campaigned for reform, while others countered the arguments of reformers.

• Public tracts and newspapers spread the new ideas and generated discussions and expressions from the public.
• 1821: Raja Ram Mohan Roy published the Sambad Kaumudi and the Hindu orthodoxy commissioned the Samachar Chandrika to oppose his opinions.
• From 1822: Two Persian newspapers were published, Jam-i-Jahan Nama and Shamsul Akhbar. A Guajarati newspaper, the Bombay Samachar, was also published.
• In North India, the ulema were deeply anxious about the collapse of Muslim dynasties. They used cheap lithographic presses, published Persian and Urdu translations of Holy Scriptures and printed religious tracts and newspapers.

Body mass index is bmi.

It is used to determine whether an adult is undernourished or not it is calculated by weight by the square of height.

It is the process of finding out a persons nutrition level. It is caculated in the following way.

1.Measure the weight of the person

2. take the height of the person

3. divide the weight by the square of the height in meters

If BMI is less than 18.5 then the person is undernourished and if it is more than 25 than it is overweight.