The gen-Xers (born between 1961 and 1980) are classified as a(n) :​

A) ​age grade
B) ​common-interest association
C) ​phratry
D) ​age set

Paleoanthropologists find the first evidences of human culture around:​

A) ​2.6 million years ago
B) ​4.4 million years ago
C) ​1.2 million years ago
D) ​3.8 million years ago