One of the most significant challenges is building an airplane had to do with "propulsion", since the technology that allowed motors to have enough energy to lift an airplane into the sky with a passenger wasn't available for most of history.
Answer:
in Birmingham, and directly paved the way for the Civil Rights Act of 1964 which prohibited racial discrimination in hiring practices and public services throughout the United States.
The answer is Uncle Tom's Cabin :D
Have a nice day~
