Life expectancy around the year 1800 was only about 36 years, so "middle age" (or median of lifespans) would be only about 17 or 18 years of age. By the time young people reached their late teens, they typically were expected to be working, married and carrying adult responsibilities.
Those life expectancy numbers can be a little misleading, though. A main reason that average life expectancy was only in the mid-30s is because infant mortality rates were very high. For persons who survived their childhood into adulthood, there was a good chance they lived to a much older age than 30-something.
1. The fact that all Incan architecture shares similar design principles suggests C. unity. - they all wanted to be the same because they were a union
2. The towers of St. Basil's Cathedral in Russia are symbolic of C. eight battles.
3. The Greek arch can typically be seen in all of these, but let's say A. bridges.
The Great Depression, it wasn't that great though.
