Questions

A primary key is a special relational database table column or combination of columns designated to uniquely identify all table records. That is, A primary key is a column or set of columns in a table that uniquely identifies tuples (rows) in that table.

A primary key, also called a Primary Keyword.

Main Features Primary key are ::

It must contain a unique value for each row of data.

It cannot contain null values.

Protested is used because here the villagers express their feeling by making an objection to what has been done.

The decentralization system was recommended by Balwant Rai Mehta.

1.Limitations on the size of data. 

2.Most Microprocessors does not support floating-point operations. 

3.Over heating physically

4. Not bit addressable

A shell is an interactive user interface to an operating system services that allows an user to enter commands as character strings or through a graphical user interface. The shell converts them to system calls to the OS or forks off a process to execute the command. System call results and other information from the OS are presented to the user through an interactive interface. Commonly used shells are sh,csh,ks etc.

Plants grow in size both in height and in grith. Enlargement  of cells already present cannot contribute much to the growth. Only addition of more and more cells could increase the size of the plant considerably.