The enactment of the Clean Air Act of 1970 (1970 CAA) resulted in a major shift in the federal government's role in air pollution control. This legislation authorized the development of comprehensive federal and state regulations to limit emissions from both stationary (industrial) sources and mobile sources.
Answer:
a) the effectiveness of mass production.
Explanation:
Henry Ford was the first car producer (Ford Industries) to use the assembly line, which allowed certain groups of workers to work on specific parts of the car, while simultaneously transferring the component throughout the groups to create a full car at the end. This allowed Ford to create large amounts of cars in short amount of time, decreasing not only cost of production, but also the cost to buy the car, further making the car more popular with the people. This cycle allowed for cheap cars, which in turn made Ford rich.
~
You don't show options, so here are the different definitions
1. "the study of past events, particularly in human affairs."
2. "the whole series of past events connected with someone or something."
3. "a continuous, typically chronological, record of important or public events or of a particular trend or institution."
We learned how to make better weapons and yk that stuff
