I think you mean the Golden Spike which is the ceremonial final spike driven by Leland Stanford to join the rails of the First Transcontinental Railroad across the US connecting the Central Pacific and Union Pacific railroads in 1869 in Promontory, Utah.
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 :)
Answer: The "North Atlantic Treaty Organization" ( " NATO " ) .& SEATO.
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Hope this helps!
Best wishes to you!
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Italian city-states like Venice and Genoa were located on the trade routes that linked the rest of western Europe with the East. Both these city-states became bustling trading centers. ... The increase of trade led to a new kind of economy. During the middle ages people traded goods for other goods.