Internal. The ultimate sources of variation, the source of new heritable characteristics in populations and species, are due to mutation and recombination in chromosomes, genes, DNA.
Zone VE is the flood insurance rate zone that corresponds to coastal areas that have additional hazards associated with storm waves. Mandatory flood insurance requirements apply. Zone X and Zone X-500 are flood insurance rate zones that are outside the flood plain or with average flood depths of less than 1 foot.
C, and X are the flood insurance rate zones that correspond to areas outside the. I-percent annual chance floodplain, areas of I-percent annual chance sheet flow flooding where average. depths are less than I foot, areas of I-percent annual chance stream flooding where the contributing drainage.