Answer:
Scarp retreat is a geological process through which the location of an escarpment changes over time.
Advantage: #1 Almost 0 emissions (very low greenhouse gas emissions).
#2 They can be sited almost anywhere unlike oil which is mostly imported
Disadvantage #1 Nuclear plants are more expensive to build and maintain.
#2 Proliferation concerns - breeder reactors yield products that could potentially be stolen and turned into an atomic weapon
The math suggests that for every parsec the rate of moving away is 71 km/s, so when two galaxies are separated by two parsecs we come to 142 km/s speed of moving away from each other. If we take the first light ever (from what is known so far) the cosmic microwave radiation, is 46 billion light-years away from us at all directions, which comes at 4,200 megaparsecs, which comes at 13.7 billion light-years, so it will come to 29,820,000 km/s. It all depends from the distance between the galaxies which is calculated by their type of colour and movement in comparison to other galaxies.
b:inland/interior regions