Answer:
The answer should be: Companies replaced hand-operated brakes with air brakes on trains.
Explanation:
You have to think how hard it was for trains to stop with hand operated brakes. Trains go fast, and not stopping in time can be dangerous. Hope this helped :)
<span>Russia was the other country which threatened Spanish settlement in western North America. Peter the Great ordered the exploration of North America and laid claim to much of the western North America coast</span>
Exploration <span>and settlement Border disputes Increased trade Problems with governance New.</span>
The middle east Gradpoint
Answer: The Constitution has been changed by basic legislation by Congress, actions taken by the President, key decisions of the Supreme Court, the activities of political parties, and ect.
Explanation: