Elastic IP addresses are for use in a specific region only and can therefore only be
remapped between instances within that region. You can use Elastic IP addresses to mask
the failure of an instance in one Availability Zone by rapidly remapping the address to
an instance in another Availability Zone
Edge Locations are used by CloudFront and are not places where you can run EC2
instances
DB subnets (groups) are used by the RDS relational database service and are not used
for running EC2 instances