What causes the differences in physical characteristics like hair color among people? different versions of genes
variations in DNA length
different numbers of chromosomes
variations in cell nucleus size

different variations of genes

Explanation:

DNA length has nothing to do with differences in physical characteristics. Chromosomes control hair color but the number and sizes of chromosomes doesn't play any sort of factor. Different variations of genes is the only answer that makes sense.

a small town is a good definition for new france in 1750. new france was the area colonized by france in north america. the area is nowadays the city of quebec in canada.

the following men who did not in the unification of italy were.

a) giuseppe mazzini

c) alexander ll

the other two men were camilo cavour and giuseppe garibaldi they the unification of italy by yielding territories in the italian unification. in 1861 italy was declared a united-nation state under the sardinian king victor immanuel ll.