Renee remembers very little about the first three years of her life. Most of what she knows from that time in her life comes from pictures and videos she has seen. Psychologists find this normal and call it:

The answer is infantile amnesia.

Explanation:

Also known as childhood amnesia, this phenomenon is described as the inability of adults to remember any events between the ages of two and four. The term is also applied for older adults who cannot easily retrieve memories from before the age of ten.

Infantile amnesia can be explained because the processes of memory (encoding, storage and retrieval) have not yet developed fully in early childhood.

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place