Why is it that 100 years ago rich had cars and poor had horses, when now everyone has cars and rich have

Because, that was when automobiles first started to get invented. Look at it this way: when a pair of nice nikes first get invented, or put in a store their really expensive right? Well its the same way with automobiles, also the metal took a lot of workers time to craft eccspecially when they did not have modern day machinery. I hoped this helped!

Because now automobiles are to expensive to buy now and comes with car notes

answer:

it caused mass african migration, african populations to grow, african empires to topple, and racism against slaves to emerge.