There were episodes of widespread famines, and also of deadly epidemics. Soil exhaustion, overpopulation, wars, diseases and climate change cause hundreds of famines in medieval Europe.<span> Around 1300, centuries of European prosperity and growth came to a halt. Famines such as </span>Great Famine of 1315–1317<span> slowly weakened the populace. Few people died of starvation because the weakest had already succumbed to a routine disease they otherwise would have survived. A plague like the </span>Black Death<span> killed its victims in one locality in a matter of days or even hours, reducing the population of some areas by half as many survivors fled.</span>
Answer:
Among the options given on the question the correct answer is option A,
It helped trains run on schedule and avoid collisions.
Explanation: The multiplex telegraph is a device which helped the train in 18th century to run without collision and on schedule.The multiplex telegraph was invented by the Granville T. Woods in 1887.
During that time the train collision was a big problem which caused lot of damage of both life and resources. The reason of the problem was the dispatchers of the train could not communicate with each other easily while controlling the rail way traffic. So the accidents were very common.
But the invention of multiplex telegraph helped the dispatchers to communicate with other dispatchers in different stations.
So, this invention made the rail road safer in 1800s by helping train to run on schedule and avoid collisions.
The hoover dam was the only successful public works project
