Questions

The earliest historic evidences of use of metal are of Chalcolithic Age or Stone-Copper Age, which covered the period from 1800 - 800 BC. This period was by the use of Copper as well as stone.

Hence, the first metal to be used in India is Copper.

1 Grand mother

1 Mother

4 Wives

4x2 = 8 Daughters

Total = 1 + 1 + 4 + 8 = 14 Female members.

Hemopoiesis begins in the red bone marrow, with hemopoietic stem cells that differentiate into myeloid and lymphoid lineages.

Myeloid stem cells give rise to all the other formed elements, including the erythrocytes; megakaryocytes that produce platelets; and a myeloblast lineage that gives rise to monocytes and three forms of granular leukocytes: neutrophils, eosinophils, and basophils.

Earth Hour is a people's movement inspiring individuals from more than 7000 cities across the globe to take a stand against climate change, making it the largest voluntary movement ever witnessed in history.

On 25 March 2017, Switch Off and Switch Onto Solar Energy

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. 

Here

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.