In 1913, the Ford Motor Company started using assembly lines to build their cars. Ford's workers could build a complete car in 93 minutes on the assembly line. Before then, it took workers many hours to build a single car by hand.
What happened to the overall supply of cars after 1913?

 - The supply went up.
 - The supply went down.
The assembly line was a new technology. The Ford Motor Company used the assembly line to build cars much faster than before. So, the overall supply of cars went up.