Mesopotamia is a Greek word which means ‘The land between the two rivers'. It was so called because the whole area of Mesopotamian civilization was planked by the two rivers, Tigers and Euphrates.
The important centres of this civilization were Sumer, Babylonia, Akkad and Assyria.

Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction.  Evolution in its contemporary meaning in biology typically refers to the changes in the proportions of biological types in a population over time (see the entries on evolutionary thought before Darwin and Darwin: from Origin of Species to Descent of Man for earlier meanings).

The degree of responsiveness of quantity demanded to changes in price of commodity is known as price elasticity of Demand. 

Characteristics of Business
(i) Economic Activity Business is considered to be an economic activity because it is
undertaken with as aim of earning money or livelihood.
(ii) Production or Procurement of Goods and Services Goods are offered to consumers after they are either produced or procured by business enterprises. Thus, every business enterprise either manufactures the goods it deals in or it acquires them from other producers, to be further sold to consumers or users.
Goods may be consumer goods like television, tea, pen, etc or capital goods like machinery, furniture, etc. Services may include facilities offered to consumers in the form of transportation, banking, electricity, etc.
(iii) Sale or Exchange of Goods and Services Business involves transfer or exchange of goods and services for value addition. If goods are produced for self consumption and not for selling purpose, it cannot be called a business activity. Cooking food at home for the family is not business, but cooking food and selling it to others in a restaurant is business. Thus, one essential characteristic of business is that there should be sale or exchange of goods or services between the seller and the buyer.
(iv) Regular Dealings in Goods and Services Business involves dealings in goods or services on a regular basis. Therefore, one single transaction of sale or purchase does not constitute business.
(v) Profit Earning The primary objective of business is to earn profit. For this businessmen make all possible efforts by increasing the volume of sales or reducing cost. It is an essential factor as growth and expansion would be possible only when a business is making profit.
(vi) Uncertainty of Return Business should not be considered as bed of roses. At every step
problems and obstacles hinder the path of success. One cannot expect the actual returns an investment as there is always a possibility of losses.

Survey Request. The first paragraph of a cover letter serves as an introduction and conveys the key point or purpose of the mailing, that is, requesting that the respondent complete and return the enclosed questionnaire and identifying what organization is conducting the survey and why.

One of the biggest limitations of accounting is that it cannot measure things/events that do not have a monetary value. If a certain factor, no matter how important, cannot be expressed in money it finds no place in accounting. Some very important qualities like management, loyalty, reputation, etc find no place on the balance sheet or the income statement.

No Future Assesment: The financial statements show the financial position of the firm on the date of preparation. The users of the statement are more interested in the future of the company in the short term and long term. However, accounting does not make any such estimates.

And due to the dynamic nature of the business environment, a lot can change between such dates. Auditors sometimes do disclose the important events occurring after the balance sheet date to rectify these limitations of accounting.

Historical Costs:Accounting often uses historical costs to measure the values. This fails to take into consideration factors such as inflation, price changes, etc. This skews the relevance of such accounting records and information. This is one of the major limitations of accounting.

Accounting Policies: There is no global standard in accounting policies. In India, we follow the Accounting Standards. Americans follow the GAAP and then there are the international standards, namely the IFRS. And if a global company operates in more than one country, there may be confusion.

Not all accounting policies follow the same line of thinking, and conflicts may arise due to this. It has long been said that the whole world must agree on uniform accounting policies but this has not happened yet.

Estimates: Sometimes in accounting estimation may be required as it is not possible to establish exact amounts. But these estimates will depend on the personal judgment of the accountant. And estimates are extremely subjective in nature. They are basically a person’s guess of future events. In accounting, there are many cases where such estimates need to be made like provision of doubtful debt, methods of depreciation, etc.

Verifiability: An audit of the financial statements does not guarantee the correctness of such statements. The auditor can only assure that the statements are free from error to the best of his judgment.

Errors and Frauds: Accounting is done by humans, so there will always be the scope of human errors. There is also the fear of possible manipulation of accounts to cover up a fraud. Since fraud is deliberate, it is that much harder to spot. This is one of the most dreaded limitations of accounting.

Questionnaire was first developed in London in 1838. This is a method of collecting data from respondents through a series of questions. It focuses more on obtaining standardized answers instead of specific answers. There are 7 different types of Questionnaires.

Schedule is another data collection technique containing statements, questions, and blank spaces to fill up the answers given by the respondents to the enumerator or interviewer. 
 

Accounting is the process by where a company's financials are recorded, summarized, analyzed, consulted and reported on. Bookkeeping is the recording part of this process, in which all of the financial transactions of the business (consisting of income and expenses) are entered into a database. An accountant is in charge of assessing and interpreting the financial data of a company, and for reporting on it. An accountant has a higher skill set than a bookkeeper, whose primary responsibility is handling the actual recording of the company’s financial transactions. A bookkeeper does not require any formal training, however a bookkeeper’s job is important. The information a bookkeeper is responsible for gathering and managing affects how an accountant will interpret the financial information of the company. Based on this information, the accountant provides recommendations to management or the company’s owners about spending, tax issues or other financial concerns.

The monetary value of an asset decreases over time due to use, wear and tear or obsolescence. This decrease is measured as depreciation. Machinery, equipment, currency are some examples of assets that are likely to depreciate over a specific period of time. Depreciation is an accounting method of allocating the cost of a tangible or physical asset over its useful life or life expectancy. Depreciation represents how much of an asset's value has been used up. Depreciation is a method used to allocate the cost of tangible assets or fixed assets over the assets' useful life. In other words, it allocates a portion of that cost to periods in which the tangible assets helped generate revenues or sales.

Flux: 

     It is the substance added to molten metals to bond with impurities that can be readily removed.

Types of flux:

Fluxes are of two types, viz, acidic flux and basic flux.

(a) Acidic flux: It is an acidic oxide (oxide of a non-metal) like SiO₂, P₂O₅, B₂O₃ (from borax). It is used to remove basic impurities like CaO, FeO, MgO etc. The acidic flux combines with a basic impurity to form a slag.

(b) Basic flux: It is a basic oxide (i.e. oxide of a metal) like CaO (obtained from limestone, CaCO₃), MgO (from magnesite. MgCO₃), haematite (Fe₂O₃) etc. It is used to remove acidic impurities like SiO₂, P₂O₅ etc. The basic flux combines with an acidic impurity to form a slag.

Thus, slag can be defined as a fusible mass, which is obtained when a flux reacts with an infusible, acidic or basic impurity present in the oxide ore.

The basic economic activities of life are production, distribution and disposition of goods and services. A society will be facing scarcity of resources during the time of fulfillment of these activities.

As such scarcity is evident, due to the availability of limited resources, and human needs having no limit. Therefore, this variation between the supply and demand leads to the formation of central problems of an economy.

The central problems of an economy revolve around these factors.

1. What to produce?
2. How to produce?
3. For whom to produce?

Limiting reagents are the substances that are completely consumed in the completion of a chemical reaction. They are also referred to as limiting agents or limiting reactants. According to the stoichiometry of chemical reactions, a fixed amount of reactants is required for the completion of the reaction. Let us consider the following reaction of formation of ammonia:

3H₂ + N₂ → 2NH₃