What are the 3 main mechanisms responsible for genetic variation

Mutations – Changing the genetic composition of gametes (germline mutation) leads to changed characteristics in offspring. Meiosis – Via either crossing over (prophase I) or independent assortment (metaphase I)

independent assortment of chromosomes, crossing over, and random fertilization.

well we can't tell you because we cant see the time give a screen shot or something.

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.