How does the process of meiosis lead to greater genetic variability

Meosis results into genetic variability through:

Fertilization, cross-over and independent assortment.

In Fertilization, the process leds to genetic diversity by allowing each parent to contribute to a specific set of genes to a zygote.This process depends on meiosis to create a haploid gametes where fertilized cells restore a diploid number.Crossing over occurs in the prophase stage of the meiosis 1 where a double chromatid homologous pairs of chromosomes exchange chromosome segments as they cross over each other.This makes genes from each parent to mix and result into a different genetic composition.Chromatid assortment happens in meosis 11 where sister chromatids separate and move to the daughter cells.The crossover that occursin meosis 1 results to non-identical chromatids in meosis 11 chromosome.

They both determine the exact age of rocks.

Yes they are correct good day