Dear Student,
a. It is the stone age and the Paleolithic period phase that covers 99% of human history. It is considered to be the oldest stone age, and is believed to extend from 2 million years ago to about 12,000 years ago.The palelithic period has been divided into Lower, Middle and Upper Palaeolithic.
b. However , many consider Bronze age as the early history of human civilization which continued till about the 7th century
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