Questions

ELISA - Enzyme-Linked Immuno Sorbent Assay.

An ELISA test may be used to diagnose: HIV, which causes AIDS.

An ELISA also called EIA, is a test that detects and measures antibodies in your blood. Antibodies are proteins that your body produces in response to harmful substances called antigens.

Sunanda K Datta-Ray

Demat means Dematerialisation of share, in simple it is an account with which a person can trade in security market without which a person cannot buy or sell any share in security market. 

C++ is not an Operating System.

An Operating System is a collection of system programs that manages all the other programs application programs in a computer as well as the allocation and use of hardware resources such as the CPU, Memory and the Hard Disk Drive.

It acts as an interface between the hardware and the user level program.

It controls and facilitates the overall operation of a computer. 

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UNIX : UNIX is a popular multi-user, multitasking operating system (OS) developed at Bell Labs.

Windows NT : Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993.

DOS : DOS is Disk Operating System. The term DOS can refer to any operating system.

C++ : C++ is a programming language and computing platform.

Hence, C++ is not an Operating System.

Fixed expenses are those expenses that do not change when there is a change in production or sales level.

Examples of Fixed Expenses are rent, insurance, payment on loans, salaries, advertising, etc...