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.
Zone A is the flood insurance rate zone that corresponds to the I-percent annual chance floodplains that are. determined in the Flood Insurance Study by approximate methods of analysis. Because detailed hydraulic. analyses are not performed for such areas, no Base Flood Elevations or depths are shown within this zone.